diff --git a/.gitattributes b/.gitattributes
new file mode 100644
index 0000000..a6e97c7
--- /dev/null
+++ b/.gitattributes
@@ -0,0 +1,8 @@
+#
+# https://help.github.com/articles/dealing-with-line-endings/
+#
+# Linux start script should use lf
+/gradlew text eol=lf
+
+# These are Windows script files and should use crlf
+*.bat text eol=crlf
\ No newline at end of file
diff --git a/.github/dependabot.yml b/.github/dependabot.yml
new file mode 100644
index 0000000..cb2d165
--- /dev/null
+++ b/.github/dependabot.yml
@@ -0,0 +1,10 @@
+version: 2
+updates:
+ - package-ecosystem: "github-actions"
+ directory: "/"
+ schedule:
+ interval: "weekly"
+ - package-ecosystem: "gradle"
+ directory: "/"
+ schedule:
+ interval: "daily"
\ No newline at end of file
diff --git a/.github/workflows/linter.yml b/.github/workflows/linter.yml
new file mode 100644
index 0000000..3dc14b4
--- /dev/null
+++ b/.github/workflows/linter.yml
@@ -0,0 +1,34 @@
+name: Lint Code Base
+
+on:
+ push:
+ branches: main
+ pull_request:
+ branches: main
+
+jobs:
+ build:
+ name: Lint Code Base
+
+ runs-on: ubuntu-latest
+
+ permissions:
+ contents: read
+ packages: read
+ statuses: write
+
+ steps:
+ - name: Checkout code
+ uses: actions/checkout@v3
+ with:
+ fetch-depth: 0
+
+ - name: Lint Code Base
+ uses: github/super-linter/slim@v5
+ env:
+ VALIDATE_JSCPD: false
+ VALIDATE_KOTLIN_ANDROID: false
+ VALIDATE_ALL_CODEBASE: false
+ DEFAULT_BRANCH: "main"
+ GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+
diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
new file mode 100644
index 0000000..5edc278
--- /dev/null
+++ b/.github/workflows/test.yml
@@ -0,0 +1,39 @@
+name: test with coverage
+on:
+ push:
+ pull_request:
+jobs:
+ build:
+ name: Build and Run Tests
+ runs-on: ${{ matrix.os }}
+
+ strategy:
+ matrix:
+ os: [ ubuntu-latest, windows-latest, macos-latest ]
+ steps:
+ - uses: actions/checkout@v3
+
+ - uses: actions/setup-java@v3
+ with:
+ distribution: temurin
+ java-version: 11
+
+ - name: Setup Gradle
+ uses: gradle/gradle-build-action@v2
+
+ - name: Build with Gradle
+ run: ./gradlew build
+
+ - name: JaCoCo Coverage Report
+ if: runner.os != 'Windows'
+ env:
+ report_path: trees/build/jacoco/report.csv
+ run: |
+ awk -F"," '{ instructions += $4 + $5; covered += $5; branches += $6 + $7; branches_covered +=$7 } END { print "Instructions covered:", covered"/"instructions, "--", 100*covered/instructions"%"; print "Branches covered:", branches_covered"/"branches, "--", 100*branches_covered/branches"%" }' "$report_path"
+
+ - uses: actions/upload-artifact@v3
+ if: ${{ github.ref == 'refs/heads/main' }}
+ with:
+ name: test-and-coverage-reports
+ path: trees/build/reports
+ retention-days: 365
\ No newline at end of file
diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..395679d
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,184 @@
+# Created by https://www.toptal.com/developers/gitignore/api/kotlin,java,gradle,intellij
+# Edit at https://www.toptal.com/developers/gitignore?templates=kotlin,java,gradle,intellij
+
+### Intellij ###
+# Covers JetBrains IDEs: IntelliJ, RubyMine, PhpStorm, AppCode, PyCharm, CLion, Android Studio, WebStorm and Rider
+# Reference: https://intellij-support.jetbrains.com/hc/en-us/articles/206544839
+
+# User-specific stuff
+.idea/**/workspace.xml
+.idea/**/tasks.xml
+.idea/**/usage.statistics.xml
+.idea/**/dictionaries
+.idea/**/shelf
+
+# AWS User-specific
+.idea/**/aws.xml
+
+# Generated files
+.idea/**/contentModel.xml
+
+# Sensitive or high-churn files
+.idea/**/dataSources/
+.idea/**/dataSources.ids
+.idea/**/dataSources.local.xml
+.idea/**/sqlDataSources.xml
+.idea/**/dynamic.xml
+.idea/**/uiDesigner.xml
+.idea/**/dbnavigator.xml
+
+# Gradle
+.idea/**/gradle.xml
+.idea/**/libraries
+
+# Gradle and Maven with auto-import
+# When using Gradle or Maven with auto-import, you should exclude module files,
+# since they will be recreated, and may cause churn. Uncomment if using
+# auto-import.
+# .idea/artifacts
+# .idea/compiler.xml
+# .idea/jarRepositories.xml
+# .idea/modules.xml
+# .idea/*.iml
+# .idea/modules
+# *.iml
+# *.ipr
+
+# CMake
+cmake-build-*/
+
+# Mongo Explorer plugin
+.idea/**/mongoSettings.xml
+
+# File-based project format
+*.iws
+
+# IntelliJ
+out/
+
+# mpeltonen/sbt-idea plugin
+.idea_modules/
+
+# JIRA plugin
+atlassian-ide-plugin.xml
+
+# Cursive Clojure plugin
+.idea/replstate.xml
+
+# SonarLint plugin
+.idea/sonarlint/
+
+# Crashlytics plugin (for Android Studio and IntelliJ)
+com_crashlytics_export_strings.xml
+crashlytics.properties
+crashlytics-build.properties
+fabric.properties
+
+# Editor-based Rest Client
+.idea/httpRequests
+
+# Android studio 3.1+ serialized cache file
+.idea/caches/build_file_checksums.ser
+
+### Intellij Patch ###
+# Comment Reason: https://github.com/joeblau/gitignore.io/issues/186#issuecomment-215987721
+
+# *.iml
+# modules.xml
+# .idea/misc.xml
+# *.ipr
+
+# Sonarlint plugin
+# https://plugins.jetbrains.com/plugin/7973-sonarlint
+.idea/**/sonarlint/
+
+# SonarQube Plugin
+# https://plugins.jetbrains.com/plugin/7238-sonarqube-community-plugin
+.idea/**/sonarIssues.xml
+
+# Markdown Navigator plugin
+# https://plugins.jetbrains.com/plugin/7896-markdown-navigator-enhanced
+.idea/**/markdown-navigator.xml
+.idea/**/markdown-navigator-enh.xml
+.idea/**/markdown-navigator/
+
+# Cache file creation bug
+# See https://youtrack.jetbrains.com/issue/JBR-2257
+.idea/$CACHE_FILE$
+
+# CodeStream plugin
+# https://plugins.jetbrains.com/plugin/12206-codestream
+.idea/codestream.xml
+
+# Azure Toolkit for IntelliJ plugin
+# https://plugins.jetbrains.com/plugin/8053-azure-toolkit-for-intellij
+.idea/**/azureSettings.xml
+
+### Java ###
+# Compiled class file
+*.class
+
+# Log file
+*.log
+
+# BlueJ files
+*.ctxt
+
+# Mobile Tools for Java (J2ME)
+.mtj.tmp/
+
+# Package Files #
+*.jar
+*.war
+*.nar
+*.ear
+*.zip
+*.tar.gz
+*.rar
+
+# virtual machine crash logs, see http://www.java.com/en/download/help/error_hotspot.xml
+hs_err_pid*
+replay_pid*
+
+### Kotlin ###
+# Compiled class file
+
+# Log file
+
+# BlueJ files
+
+# Mobile Tools for Java (J2ME)
+
+# Package Files #
+
+# virtual machine crash logs, see http://www.java.com/en/download/help/error_hotspot.xml
+
+### Gradle ###
+.gradle
+**/build/
+!src/**/build/
+
+# Ignore Gradle GUI config
+gradle-app.setting
+
+# Avoid ignoring Gradle wrapper jar file (.jar files are usually ignored)
+!gradle-wrapper.jar
+
+# Avoid ignore Gradle wrappper properties
+!gradle-wrapper.properties
+
+# Cache of project
+.gradletasknamecache
+
+# Eclipse Gradle plugin generated files
+# Eclipse Core
+.project
+# JDT-specific (Eclipse Java Development Tools)
+.classpath
+
+### Gradle Patch ###
+# Java heap dump
+*.hprof
+### mac gabage files
+.DS_Store
+# End of https://www.toptal.com/developers/gitignore/api/kotlin,java,gradle,intellij
diff --git a/LICENSE b/LICENSE
new file mode 100644
index 0000000..f288702
--- /dev/null
+++ b/LICENSE
@@ -0,0 +1,674 @@
+ GNU GENERAL PUBLIC LICENSE
+ Version 3, 29 June 2007
+
+ Copyright (C) 2007 Free Software Foundation, Inc.
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+ Preamble
+
+ The GNU General Public License is a free, copyleft license for
+software and other kinds of works.
+
+ The licenses for most software and other practical works are designed
+to take away your freedom to share and change the works. By contrast,
+the GNU General Public License is intended to guarantee your freedom to
+share and change all versions of a program--to make sure it remains free
+software for all its users. We, the Free Software Foundation, use the
+GNU General Public License for most of our software; it applies also to
+any other work released this way by its authors. You can apply it to
+your programs, too.
+
+ When we speak of free software, we are referring to freedom, not
+price. Our General Public Licenses are designed to make sure that you
+have the freedom to distribute copies of free software (and charge for
+them if you wish), that you receive source code or can get it if you
+want it, that you can change the software or use pieces of it in new
+free programs, and that you know you can do these things.
+
+ To protect your rights, we need to prevent others from denying you
+these rights or asking you to surrender the rights. Therefore, you have
+certain responsibilities if you distribute copies of the software, or if
+you modify it: responsibilities to respect the freedom of others.
+
+ For example, if you distribute copies of such a program, whether
+gratis or for a fee, you must pass on to the recipients the same
+freedoms that you received. You must make sure that they, too, receive
+or can get the source code. And you must show them these terms so they
+know their rights.
+
+ Developers that use the GNU GPL protect your rights with two steps:
+(1) assert copyright on the software, and (2) offer you this License
+giving you legal permission to copy, distribute and/or modify it.
+
+ For the developers' and authors' protection, the GPL clearly explains
+that there is no warranty for this free software. For both users' and
+authors' sake, the GPL requires that modified versions be marked as
+changed, so that their problems will not be attributed erroneously to
+authors of previous versions.
+
+ Some devices are designed to deny users access to install or run
+modified versions of the software inside them, although the manufacturer
+can do so. This is fundamentally incompatible with the aim of
+protecting users' freedom to change the software. The systematic
+pattern of such abuse occurs in the area of products for individuals to
+use, which is precisely where it is most unacceptable. Therefore, we
+have designed this version of the GPL to prohibit the practice for those
+products. If such problems arise substantially in other domains, we
+stand ready to extend this provision to those domains in future versions
+of the GPL, as needed to protect the freedom of users.
+
+ Finally, every program is threatened constantly by software patents.
+States should not allow patents to restrict development and use of
+software on general-purpose computers, but in those that do, we wish to
+avoid the special danger that patents applied to a free program could
+make it effectively proprietary. To prevent this, the GPL assures that
+patents cannot be used to render the program non-free.
+
+ The precise terms and conditions for copying, distribution and
+modification follow.
+
+ TERMS AND CONDITIONS
+
+ 0. Definitions.
+
+ "This License" refers to version 3 of the GNU General Public License.
+
+ "Copyright" also means copyright-like laws that apply to other kinds of
+works, such as semiconductor masks.
+
+ "The Program" refers to any copyrightable work licensed under this
+License. Each licensee is addressed as "you". "Licensees" and
+"recipients" may be individuals or organizations.
+
+ To "modify" a work means to copy from or adapt all or part of the work
+in a fashion requiring copyright permission, other than the making of an
+exact copy. The resulting work is called a "modified version" of the
+earlier work or a work "based on" the earlier work.
+
+ A "covered work" means either the unmodified Program or a work based
+on the Program.
+
+ To "propagate" a work means to do anything with it that, without
+permission, would make you directly or secondarily liable for
+infringement under applicable copyright law, except executing it on a
+computer or modifying a private copy. Propagation includes copying,
+distribution (with or without modification), making available to the
+public, and in some countries other activities as well.
+
+ To "convey" a work means any kind of propagation that enables other
+parties to make or receive copies. Mere interaction with a user through
+a computer network, with no transfer of a copy, is not conveying.
+
+ An interactive user interface displays "Appropriate Legal Notices"
+to the extent that it includes a convenient and prominently visible
+feature that (1) displays an appropriate copyright notice, and (2)
+tells the user that there is no warranty for the work (except to the
+extent that warranties are provided), that licensees may convey the
+work under this License, and how to view a copy of this License. If
+the interface presents a list of user commands or options, such as a
+menu, a prominent item in the list meets this criterion.
+
+ 1. Source Code.
+
+ The "source code" for a work means the preferred form of the work
+for making modifications to it. "Object code" means any non-source
+form of a work.
+
+ A "Standard Interface" means an interface that either is an official
+standard defined by a recognized standards body, or, in the case of
+interfaces specified for a particular programming language, one that
+is widely used among developers working in that language.
+
+ The "System Libraries" of an executable work include anything, other
+than the work as a whole, that (a) is included in the normal form of
+packaging a Major Component, but which is not part of that Major
+Component, and (b) serves only to enable use of the work with that
+Major Component, or to implement a Standard Interface for which an
+implementation is available to the public in source code form. A
+"Major Component", in this context, means a major essential component
+(kernel, window system, and so on) of the specific operating system
+(if any) on which the executable work runs, or a compiler used to
+produce the work, or an object code interpreter used to run it.
+
+ The "Corresponding Source" for a work in object code form means all
+the source code needed to generate, install, and (for an executable
+work) run the object code and to modify the work, including scripts to
+control those activities. However, it does not include the work's
+System Libraries, or general-purpose tools or generally available free
+programs which are used unmodified in performing those activities but
+which are not part of the work. For example, Corresponding Source
+includes interface definition files associated with source files for
+the work, and the source code for shared libraries and dynamically
+linked subprograms that the work is specifically designed to require,
+such as by intimate data communication or control flow between those
+subprograms and other parts of the work.
+
+ The Corresponding Source need not include anything that users
+can regenerate automatically from other parts of the Corresponding
+Source.
+
+ The Corresponding Source for a work in source code form is that
+same work.
+
+ 2. Basic Permissions.
+
+ All rights granted under this License are granted for the term of
+copyright on the Program, and are irrevocable provided the stated
+conditions are met. This License explicitly affirms your unlimited
+permission to run the unmodified Program. The output from running a
+covered work is covered by this License only if the output, given its
+content, constitutes a covered work. This License acknowledges your
+rights of fair use or other equivalent, as provided by copyright law.
+
+ You may make, run and propagate covered works that you do not
+convey, without conditions so long as your license otherwise remains
+in force. You may convey covered works to others for the sole purpose
+of having them make modifications exclusively for you, or provide you
+with facilities for running those works, provided that you comply with
+the terms of this License in conveying all material for which you do
+not control copyright. Those thus making or running the covered works
+for you must do so exclusively on your behalf, under your direction
+and control, on terms that prohibit them from making any copies of
+your copyrighted material outside their relationship with you.
+
+ Conveying under any other circumstances is permitted solely under
+the conditions stated below. Sublicensing is not allowed; section 10
+makes it unnecessary.
+
+ 3. Protecting Users' Legal Rights From Anti-Circumvention Law.
+
+ No covered work shall be deemed part of an effective technological
+measure under any applicable law fulfilling obligations under article
+11 of the WIPO copyright treaty adopted on 20 December 1996, or
+similar laws prohibiting or restricting circumvention of such
+measures.
+
+ When you convey a covered work, you waive any legal power to forbid
+circumvention of technological measures to the extent such circumvention
+is effected by exercising rights under this License with respect to
+the covered work, and you disclaim any intention to limit operation or
+modification of the work as a means of enforcing, against the work's
+users, your or third parties' legal rights to forbid circumvention of
+technological measures.
+
+ 4. Conveying Verbatim Copies.
+
+ You may convey verbatim copies of the Program's source code as you
+receive it, in any medium, provided that you conspicuously and
+appropriately publish on each copy an appropriate copyright notice;
+keep intact all notices stating that this License and any
+non-permissive terms added in accord with section 7 apply to the code;
+keep intact all notices of the absence of any warranty; and give all
+recipients a copy of this License along with the Program.
+
+ You may charge any price or no price for each copy that you convey,
+and you may offer support or warranty protection for a fee.
+
+ 5. Conveying Modified Source Versions.
+
+ You may convey a work based on the Program, or the modifications to
+produce it from the Program, in the form of source code under the
+terms of section 4, provided that you also meet all of these conditions:
+
+ a) The work must carry prominent notices stating that you modified
+ it, and giving a relevant date.
+
+ b) The work must carry prominent notices stating that it is
+ released under this License and any conditions added under section
+ 7. This requirement modifies the requirement in section 4 to
+ "keep intact all notices".
+
+ c) You must license the entire work, as a whole, under this
+ License to anyone who comes into possession of a copy. This
+ License will therefore apply, along with any applicable section 7
+ additional terms, to the whole of the work, and all its parts,
+ regardless of how they are packaged. This License gives no
+ permission to license the work in any other way, but it does not
+ invalidate such permission if you have separately received it.
+
+ d) If the work has interactive user interfaces, each must display
+ Appropriate Legal Notices; however, if the Program has interactive
+ interfaces that do not display Appropriate Legal Notices, your
+ work need not make them do so.
+
+ A compilation of a covered work with other separate and independent
+works, which are not by their nature extensions of the covered work,
+and which are not combined with it such as to form a larger program,
+in or on a volume of a storage or distribution medium, is called an
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+used to limit the access or legal rights of the compilation's users
+beyond what the individual works permit. Inclusion of a covered work
+in an aggregate does not cause this License to apply to the other
+parts of the aggregate.
+
+ 6. Conveying Non-Source Forms.
+
+ You may convey a covered work in object code form under the terms
+of sections 4 and 5, provided that you also convey the
+machine-readable Corresponding Source under the terms of this License,
+in one of these ways:
+
+ a) Convey the object code in, or embodied in, a physical product
+ (including a physical distribution medium), accompanied by the
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+ customarily used for software interchange.
+
+ b) Convey the object code in, or embodied in, a physical product
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+ written offer, valid for at least three years and valid for as
+ long as you offer spare parts or customer support for that product
+ model, to give anyone who possesses the object code either (1) a
+ copy of the Corresponding Source for all the software in the
+ product that is covered by this License, on a durable physical
+ medium customarily used for software interchange, for a price no
+ more than your reasonable cost of physically performing this
+ conveying of source, or (2) access to copy the
+ Corresponding Source from a network server at no charge.
+
+ c) Convey individual copies of the object code with a copy of the
+ written offer to provide the Corresponding Source. This
+ alternative is allowed only occasionally and noncommercially, and
+ only if you received the object code with such an offer, in accord
+ with subsection 6b.
+
+ d) Convey the object code by offering access from a designated
+ place (gratis or for a charge), and offer equivalent access to the
+ Corresponding Source in the same way through the same place at no
+ further charge. You need not require recipients to copy the
+ Corresponding Source along with the object code. If the place to
+ copy the object code is a network server, the Corresponding Source
+ may be on a different server (operated by you or a third party)
+ that supports equivalent copying facilities, provided you maintain
+ clear directions next to the object code saying where to find the
+ Corresponding Source. Regardless of what server hosts the
+ Corresponding Source, you remain obligated to ensure that it is
+ available for as long as needed to satisfy these requirements.
+
+ e) Convey the object code using peer-to-peer transmission, provided
+ you inform other peers where the object code and Corresponding
+ Source of the work are being offered to the general public at no
+ charge under subsection 6d.
+
+ A separable portion of the object code, whose source code is excluded
+from the Corresponding Source as a System Library, need not be
+included in conveying the object code work.
+
+ A "User Product" is either (1) a "consumer product", which means any
+tangible personal property which is normally used for personal, family,
+or household purposes, or (2) anything designed or sold for incorporation
+into a dwelling. In determining whether a product is a consumer product,
+doubtful cases shall be resolved in favor of coverage. For a particular
+product received by a particular user, "normally used" refers to a
+typical or common use of that class of product, regardless of the status
+of the particular user or of the way in which the particular user
+actually uses, or expects or is expected to use, the product. A product
+is a consumer product regardless of whether the product has substantial
+commercial, industrial or non-consumer uses, unless such uses represent
+the only significant mode of use of the product.
+
+ "Installation Information" for a User Product means any methods,
+procedures, authorization keys, or other information required to install
+and execute modified versions of a covered work in that User Product from
+a modified version of its Corresponding Source. The information must
+suffice to ensure that the continued functioning of the modified object
+code is in no case prevented or interfered with solely because
+modification has been made.
+
+ If you convey an object code work under this section in, or with, or
+specifically for use in, a User Product, and the conveying occurs as
+part of a transaction in which the right of possession and use of the
+User Product is transferred to the recipient in perpetuity or for a
+fixed term (regardless of how the transaction is characterized), the
+Corresponding Source conveyed under this section must be accompanied
+by the Installation Information. But this requirement does not apply
+if neither you nor any third party retains the ability to install
+modified object code on the User Product (for example, the work has
+been installed in ROM).
+
+ The requirement to provide Installation Information does not include a
+requirement to continue to provide support service, warranty, or updates
+for a work that has been modified or installed by the recipient, or for
+the User Product in which it has been modified or installed. Access to a
+network may be denied when the modification itself materially and
+adversely affects the operation of the network or violates the rules and
+protocols for communication across the network.
+
+ Corresponding Source conveyed, and Installation Information provided,
+in accord with this section must be in a format that is publicly
+documented (and with an implementation available to the public in
+source code form), and must require no special password or key for
+unpacking, reading or copying.
+
+ 7. Additional Terms.
+
+ "Additional permissions" are terms that supplement the terms of this
+License by making exceptions from one or more of its conditions.
+Additional permissions that are applicable to the entire Program shall
+be treated as though they were included in this License, to the extent
+that they are valid under applicable law. If additional permissions
+apply only to part of the Program, that part may be used separately
+under those permissions, but the entire Program remains governed by
+this License without regard to the additional permissions.
+
+ When you convey a copy of a covered work, you may at your option
+remove any additional permissions from that copy, or from any part of
+it. (Additional permissions may be written to require their own
+removal in certain cases when you modify the work.) You may place
+additional permissions on material, added by you to a covered work,
+for which you have or can give appropriate copyright permission.
+
+ Notwithstanding any other provision of this License, for material you
+add to a covered work, you may (if authorized by the copyright holders of
+that material) supplement the terms of this License with terms:
+
+ a) Disclaiming warranty or limiting liability differently from the
+ terms of sections 15 and 16 of this License; or
+
+ b) Requiring preservation of specified reasonable legal notices or
+ author attributions in that material or in the Appropriate Legal
+ Notices displayed by works containing it; or
+
+ c) Prohibiting misrepresentation of the origin of that material, or
+ requiring that modified versions of such material be marked in
+ reasonable ways as different from the original version; or
+
+ d) Limiting the use for publicity purposes of names of licensors or
+ authors of the material; or
+
+ e) Declining to grant rights under trademark law for use of some
+ trade names, trademarks, or service marks; or
+
+ f) Requiring indemnification of licensors and authors of that
+ material by anyone who conveys the material (or modified versions of
+ it) with contractual assumptions of liability to the recipient, for
+ any liability that these contractual assumptions directly impose on
+ those licensors and authors.
+
+ All other non-permissive additional terms are considered "further
+restrictions" within the meaning of section 10. If the Program as you
+received it, or any part of it, contains a notice stating that it is
+governed by this License along with a term that is a further
+restriction, you may remove that term. If a license document contains
+a further restriction but permits relicensing or conveying under this
+License, you may add to a covered work material governed by the terms
+of that license document, provided that the further restriction does
+not survive such relicensing or conveying.
+
+ If you add terms to a covered work in accord with this section, you
+must place, in the relevant source files, a statement of the
+additional terms that apply to those files, or a notice indicating
+where to find the applicable terms.
+
+ Additional terms, permissive or non-permissive, may be stated in the
+form of a separately written license, or stated as exceptions;
+the above requirements apply either way.
+
+ 8. Termination.
+
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+
+ Nothing in this License shall be construed as excluding or limiting
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+
+ 12. No Surrender of Others' Freedom.
+
+ If conditions are imposed on you (whether by court order, agreement or
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+ 13. Use with the GNU Affero General Public License.
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+ 14. Revised Versions of this License.
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+be similar in spirit to the present version, but may differ in detail to
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+
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+ 15. Disclaimer of Warranty.
+
+ THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY
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+ 17. Interpretation of Sections 15 and 16.
+
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+an absolute waiver of all civil liability in connection with the
+Program, unless a warranty or assumption of liability accompanies a
+copy of the Program in return for a fee.
+
+ END OF TERMS AND CONDITIONS
+
+ How to Apply These Terms to Your New Programs
+
+ If you develop a new program, and you want it to be of the greatest
+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these terms.
+
+ To do so, attach the following notices to the program. It is safest
+to attach them to the start of each source file to most effectively
+state the exclusion of warranty; and each file should have at least
+the "copyright" line and a pointer to where the full notice is found.
+
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+
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+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation, either version 3 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
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+ along with this program. If not, see .
+
+Also add information on how to contact you by electronic and paper mail.
+
+ If the program does terminal interaction, make it output a short
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+ This is free software, and you are welcome to redistribute it
+ under certain conditions; type `show c' for details.
+
+The hypothetical commands `show w' and `show c' should show the appropriate
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+might be different; for a GUI interface, you would use an "about box".
+
+ You should also get your employer (if you work as a programmer) or school,
+if any, to sign a "copyright disclaimer" for the program, if necessary.
+For more information on this, and how to apply and follow the GNU GPL, see
+.
+
+ The GNU General Public License does not permit incorporating your program
+into proprietary programs. If your program is a subroutine library, you
+may consider it more useful to permit linking proprietary applications with
+the library. If this is what you want to do, use the GNU Lesser General
+Public License instead of this License. But first, please read
+.
diff --git a/README.md b/README.md
new file mode 100644
index 0000000..6d981b3
--- /dev/null
+++ b/README.md
@@ -0,0 +1,77 @@
+# Binary search trees library
+> An open source library written in Kotlin to work with data structures such as AVL tree, red-black tree, and binary search tree.
+## 🖍 Used technology
+![Kotlin](https://img.shields.io/badge/-Kotlin-61DAFB?logo=kotlin)
+![Junit](https://img.shields.io/badge/Tests-Junit-green)
+![Neo4j](https://img.shields.io/badge/Neo4j-008CC1?style=for-the-badge&logo=neo4j&logoColor=white)
+![Postgresql](https://img.shields.io/badge/PostgreSQL-316192?style=for-the-badge&logo=postgresql&logoColor=white)
+![Docker](https://img.shields.io/badge/Docker-316192?style=for-the-badge&logo=Docker&logoColor=white)
+## :package: Getting started
+To build the library run
+
+```sh
+./gradlew build
+```
+To run PostgreSQL with docker:
+```sh
+./start-db.sh
+```
+or
+```sh
+./start-db.bat
+```
+
+## Using binary search trees
+Any data (provided with `Comparable` key) can be stored in trees.
+For example:
+
+```kotlin
+ import bst.BSTree
+ val tree = BSTree(1, "apple")
+ tree.insert(7, "orange")
+ tree.insert(28, "Alice")
+ tree.insert(4, "Bob")
+```
+Constructor takes two arguments: `key` and `value`, thus instantiating a root node (you can delete it,
+but you cannot create an empty tree).
+`insert` method also takes same arguments and adds a node with specified `key` and `value` properties to the tree.
+Method `setName` allows you to set the name of a tree.
+
+Find or remove element from tree:
+```kotlin
+ tree.find(4) // returns "Bob"
+ tree.remove(1)
+```
+`find` and `remove` methods take some `Comparable` key as an argument.
+
+AVL and red-black trees implement the same methods.
+
+## Storing binary search trees
+AVL tree can be saved to and loaded from JSON file.
+For example:
+```kotlin
+ val tree = AVLTree(1, "apple")
+ tree.setName("test")
+ val controller = JsonController()
+ controller.saveTreeToJson(test)
+ println(controller.readFromJson("test")?.treeName)
+```
+You can also save binary search tree to SQL database:
+```kotlin
+ val tree = BSTree(1, "apple")
+ tree.setName("test")
+ val controller = SQLController()
+ controller.saveTreeToDB(test_data)
+ val remTree = controller.getTree("test")
+```
+And you can save red-black tree to Neo4j database
+```kotlin
+ val tree = RedBlackTree(1, "apple")
+ tree.setName("test")
+ val controller = Neoj4Conroller()
+ contoller.saveTree(tree)
+ val remTree = controller.loadTree("test")
+```
+
+An example of interacting with trees through a graphical interface
+![Example gif](https://github.com/spbu-coding-2022/trees-3/blob/add-ui/readme_gif/example1.gif)
\ No newline at end of file
diff --git a/app/build.gradle.kts b/app/build.gradle.kts
new file mode 100644
index 0000000..b24ba3a
--- /dev/null
+++ b/app/build.gradle.kts
@@ -0,0 +1,25 @@
+plugins {
+ id("org.jetbrains.kotlin.jvm") version "1.8.10"
+ id("org.openjfx.javafxplugin") version "0.0.12"
+ application
+}
+
+javafx {
+ version = "18"
+ modules("javafx.controls", "javafx.fxml")
+}
+
+repositories {
+ // Use Maven Central for resolving dependencies.
+ mavenCentral()
+}
+
+dependencies {
+ implementation("no.tornado:tornadofx:1.7.20")
+ implementation(project(":trees"))
+}
+
+application {
+ // Define the main class for the application.
+ mainClass.set("app.AppKt")
+}
diff --git a/app/src/main/kotlin/app/App.kt b/app/src/main/kotlin/app/App.kt
new file mode 100644
index 0000000..8a2e6bf
--- /dev/null
+++ b/app/src/main/kotlin/app/App.kt
@@ -0,0 +1,19 @@
+package app
+
+import app.view.MainView
+import tornadofx.App
+import tornadofx.launch
+
+/**
+ * Represents the main application class.
+ */
+
+class MyApp : App(MainView::class)
+
+/**
+ * The main entry point of the application.
+ */
+
+fun main() {
+ launch()
+}
diff --git a/app/src/main/kotlin/app/controller/AVLController.kt b/app/src/main/kotlin/app/controller/AVLController.kt
new file mode 100644
index 0000000..03f2a8e
--- /dev/null
+++ b/app/src/main/kotlin/app/controller/AVLController.kt
@@ -0,0 +1,196 @@
+package app.controller
+
+import bst.AVLTree
+import bst.db.controllers.JsonController
+import bst.nodes.AVLNode
+import javafx.collections.FXCollections
+import javafx.collections.ObservableList
+import javafx.scene.control.Tooltip
+import javafx.scene.layout.Pane
+import javafx.scene.layout.StackPane
+import javafx.scene.paint.Color
+import javafx.scene.shape.Circle
+import javafx.scene.shape.Line
+import javafx.scene.text.Text
+import javafx.scene.text.TextBoundsType
+import tornadofx.Controller
+import kotlin.math.min
+
+/**
+ * The AVLController class is responsible for managing AVL trees.
+ *
+ * It extends the Controller class and provides additional functionality for working with AVL trees.
+ */
+
+class AVLController : Controller() {
+
+ /**
+ * Returns a Boolean value indicating whether the given String can be converted to an Integer.
+ *
+ * @param s the String to be checked
+ * @return true if the String can be converted to an Integer, false otherwise
+ */
+
+ fun isNumeric(s: String): Boolean {
+ return try {
+ s.toInt()
+ true
+ } catch (e: NumberFormatException) {
+ false
+ }
+ }
+
+ /**
+ * Inserts a new node with the given key and value into the AVL Tree and redraws the tree in the tree pane.
+ *
+ * @param tree the AVL Tree to insert the node into
+ * @param treePane the Pane where the AVL Tree is displayed
+ * @param key the key of the new node to be inserted
+ * @param value the value of the new node to be inserted
+ */
+
+ fun insertNode(tree: AVLTree, treePane: Pane, key: Int, value: String) {
+ tree.insert(key, value)
+ drawTree(tree, treePane)
+ }
+
+ /**
+ * Clears all nodes from the AVL Tree and removes all nodes from the tree pane.
+ *
+ * @param tree the AVL Tree to be cleared
+ * @param treePane the Pane where the AVL Tree is displayed
+ */
+
+ fun clearTree(tree: AVLTree, treePane: Pane) {
+ tree.clear()
+ treePane.children.clear()
+ }
+
+ /**
+ * Draws the AVL Tree in the tree pane.
+ *
+ * @param tree the AVL Tree to be drawn
+ * @param treePane the Pane where the AVL Tree is displayed
+ */
+
+ fun drawTree(tree: AVLTree, treePane: Pane) {
+ treePane.children.clear()
+ val root = tree.getRoot()
+ if (root != null) {
+ drawNode(root, treePane, treePane.width / 2.0, treePane.width / 2.0, 250.0)
+ }
+ }
+
+ /**
+ * Draws the given [AVLNode] in the [treePane] at the specified [x] and [y] coordinates with the given [offsetX].
+ * @param node the [AVLNode] to be drawn
+ * @param treePane the [Pane] in which the [AVLNode] is to be drawn
+ * @param x the x-coordinate of the [AVLNode] in the [treePane]
+ * @param y the y-coordinate of the [AVLNode] in the [treePane]
+ * @param offsetX the horizontal offset from the [x] coordinate at which the [AVLNode] should be drawn
+ */
+
+ private fun drawNode(node: AVLNode, treePane: Pane, x: Double, y: Double, offsetX: Double) {
+ val circleRadius = 20.0
+ val circle = Circle(circleRadius)
+ circle.fill = Color.WHITE
+ circle.stroke = Color.BLACK
+
+ val nodeText = Text(node.key.toString())
+ nodeText.boundsType = TextBoundsType.VISUAL
+
+ val scale =
+ min(circleRadius * 1.3 / nodeText.boundsInLocal.width, circleRadius * 1.3 / nodeText.boundsInLocal.height)
+ nodeText.scaleX = scale
+ nodeText.scaleY = scale
+
+ val nodeStackPane = StackPane(circle, nodeText)
+ nodeStackPane.relocate(x - circleRadius, y - circleRadius)
+
+ val tooltip = Tooltip("value: ${node.value}")
+ Tooltip.install(nodeStackPane, tooltip)
+
+ treePane.children.add(nodeStackPane)
+
+ if (node.left != null) {
+ val leftX = x - offsetX
+ val leftY = y + 50
+ val leftLine = Line(x, y + circleRadius, leftX, leftY - circleRadius)
+ treePane.children.add(leftLine)
+ drawNode(node.left!!, treePane, leftX, leftY, offsetX / 2.0)
+ }
+
+ if (node.right != null) {
+ val rightX = x + offsetX
+ val rightY = y + 50
+ val rightLine = Line(x, y + circleRadius, rightX, rightY - circleRadius)
+ treePane.children.add(rightLine)
+ drawNode(node.right!!, treePane, rightX, rightY, offsetX / 2.0)
+ }
+ }
+
+ /**
+ * Retrieves a list of all tree names from the JSON controller.
+ *
+ * @return An observable list of tree names.
+ */
+
+ fun getTreesList(): ObservableList? {
+ val controller = JsonController()
+ val treeNames = controller.getAllTrees()
+ val values = FXCollections.observableArrayList()
+ treeNames.forEach {
+ values.add(it)
+ }
+ return values
+ }
+
+ /**
+ * Retrieves an AVL tree with the given name from the JSON controller.
+ *
+ * @param name The name of the tree to retrieve.
+ * @return The AVL tree with the given name, or null if it doesn't exist.
+ */
+
+ fun getTreeFromJson(name: String): AVLTree? {
+ val controller = JsonController()
+ return controller.getTree(name)
+ }
+
+ /**
+ * Removes the AVL tree with the given name from the JSON controller.
+ *
+ * @param name The name of the tree to remove.
+ */
+
+ fun deleteTreeFromDB(name: String) {
+ JsonController().run {
+ removeTree(name)
+ }
+ }
+
+ /**
+ * Saves the given AVL tree to the JSON controller with the given name.
+ *
+ * @param tree The AVL tree to save.
+ * @param treeName The name to use when saving the tree.
+ */
+
+ fun saveTree(tree: AVLTree, treeName: String) {
+ val controller = JsonController()
+ controller.saveTree(tree, treeName)
+ }
+
+ /**
+ * Removes a node with the given value from the given AVL tree and redraws the tree on the given pane.
+ *
+ * @param value The value of the node to remove.
+ * @param tree The AVL tree to remove the node from.
+ * @param treePane The pane where the tree is to be drawn.
+ */
+
+ fun deleteNode(value: Int, tree: AVLTree, treePane: Pane) {
+ tree.remove(value)
+ drawTree(tree, treePane)
+ }
+}
diff --git a/app/src/main/kotlin/app/controller/BSTController.kt b/app/src/main/kotlin/app/controller/BSTController.kt
new file mode 100644
index 0000000..b4ca510
--- /dev/null
+++ b/app/src/main/kotlin/app/controller/BSTController.kt
@@ -0,0 +1,215 @@
+package app.controller
+
+import bst.BSTree
+import bst.db.controllers.SQLController
+import bst.nodes.BSTNode
+import javafx.collections.FXCollections.observableArrayList
+import javafx.collections.ObservableList
+import javafx.scene.control.Tooltip
+import javafx.scene.layout.Pane
+import javafx.scene.layout.StackPane
+import javafx.scene.paint.Color
+import javafx.scene.shape.Circle
+import javafx.scene.shape.Line
+import javafx.scene.text.Text
+import javafx.scene.text.TextBoundsType
+import tornadofx.Controller
+import kotlin.math.min
+
+/**
+ * The BSTController class is responsible for managing binary search trees.
+ *
+ * It extends the Controller class and provides additional functionality for working with binary search trees.
+ */
+
+class BSTController : Controller() {
+
+ /**
+ * Determines whether a given string can be parsed as an integer.
+ *
+ * @param s The string to check.
+ * @return True if the string can be parsed as an integer, false otherwise.
+ */
+
+ fun isNumeric(s: String): Boolean {
+ return try {
+ s.toInt()
+ true
+ } catch (e: NumberFormatException) {
+ false
+ }
+ }
+
+ /**
+ * Inserts a new node with the given key and value into the given binary search tree and redraws the tree on the given pane.
+ *
+ * @param tree The binary search tree to insert the node into.
+ * @param treePane The pane where the tree is to be drawn.
+ * @param key The key of the new node to insert.
+ * @param value The value of the new node to insert.
+ */
+
+ fun insertNode(tree: BSTree, treePane: Pane, key: Int, value: String) {
+ tree.insert(key, value)
+ drawTree(tree, treePane)
+ }
+
+ /**
+ * Clears the given binary search tree and removes all nodes from the given pane.
+ *
+ * @param tree The binary search tree to clear.
+ * @param treePane The pane where the tree is to be drawn.
+ */
+
+ fun clearTree(tree: BSTree, treePane: Pane) {
+ tree.clear()
+ treePane.children.clear()
+ }
+
+ /**
+ * Draws the given binary search tree on the given pane.
+ *
+ * @param tree The binary search tree to draw.
+ * @param treePane The pane where the tree is to be drawn.
+ */
+
+ fun drawTree(tree: BSTree, treePane: Pane) {
+ treePane.children.clear()
+ val root = tree.getRoot()
+ if (root != null) {
+ drawNode(root, treePane, treePane.width / 2.0, treePane.width / 2.0, 250.0)
+ }
+ }
+
+ /**
+ * Draws a binary search tree node on a given tree pane at a specific position with a given offset.
+ *
+ * @param node The binary search tree node to draw.
+ * @param treePane The pane where the tree is to be drawn.
+ * @param x The x-coordinate of the node to draw.
+ * @param y The y-coordinate of the node to draw.
+ * @param offsetX The offset to apply to the x-coordinate of child nodes.
+ */
+
+ private fun drawNode(node: BSTNode, treePane: Pane, x: Double, y: Double, offsetX: Double) {
+ // Create a circle to represent the node
+ val circleRadius = 20.0
+ val circle = Circle(circleRadius)
+ circle.fill = Color.WHITE
+ circle.stroke = Color.BLACK
+
+ // Create a text label to display the node's key
+ val nodeText = Text(node.key.toString())
+ nodeText.boundsType = TextBoundsType.VISUAL
+
+ // Scale the text label to fit inside the circle
+ val scale =
+ min(circleRadius * 1.3 / nodeText.boundsInLocal.width, circleRadius * 1.3 / nodeText.boundsInLocal.height)
+ nodeText.scaleX = scale
+ nodeText.scaleY = scale
+
+ // Combine the circle and text label into a StackPane
+ val nodeStackPane = StackPane(circle, nodeText)
+ nodeStackPane.relocate(x - circleRadius, y - circleRadius)
+
+ // Add a tooltip to the StackPane to display the node's value
+ val tooltip = Tooltip("value: ${node.value}")
+ Tooltip.install(nodeStackPane, tooltip)
+
+ // Add the StackPane to the tree pane
+ treePane.children.add(nodeStackPane)
+
+ // If the node has a left child, draw it recursively
+ if (node.left != null) {
+ val leftX = x - offsetX
+ val leftY = y + 50
+ val leftLine = Line(x, y + circleRadius, leftX, leftY - circleRadius)
+ treePane.children.add(leftLine)
+ drawNode(node.left!!, treePane, leftX, leftY, offsetX / 2.0)
+ }
+
+ // If the node has a right child, draw it recursively
+ if (node.right != null) {
+ val rightX = x + offsetX
+ val rightY = y + 50
+ val rightLine = Line(x, y + circleRadius, rightX, rightY - circleRadius)
+ treePane.children.add(rightLine)
+ drawNode(node.right!!, treePane, rightX, rightY, offsetX / 2.0)
+ }
+ }
+
+ /**
+ * @return An ObservableList of tree names, or null if there are no trees in the database.
+ */
+
+ fun getTreesList(): ObservableList? {
+ // Creates a new SQLController object.
+ val controller = SQLController()
+ // Retrieves all tree names from the database.
+ val treeNames = controller.getAllTrees()
+ // Converts the list of tree names to an ObservableList.
+ val values = observableArrayList()
+ treeNames.forEach {
+ values.add(it)
+ }
+ // Returns the ObservableList of tree names.
+ return values
+ }
+
+ /**
+ * Retrieves a binary search tree with the given name from the database.
+ *
+ * @param name The name of the binary search tree to retrieve.
+ * @return The binary search tree with the given name, or null if it does not exist in the database.
+ */
+
+ fun getTreeFromDB(name: String): BSTree? {
+ // Creates a new SQLController object.
+ val controller = SQLController()
+ // Retrieves the binary search tree with the given name from the database.
+ val tree = controller.getTree(name)
+ // Returns the binary search tree.
+ return tree
+ }
+
+ /**
+ * Removes the binary search tree with the given name from the database.
+ *
+ * @param name The name of the binary search tree to remove.
+ */
+
+ fun deleteTreeFromDB(name: String) {
+ // Creates a new SQLController object and removes the binary search tree with the given name from the database.
+ SQLController().run {
+ removeTree(name)
+ }
+ }
+
+ /**
+ * Saves a binary search tree to the database with the given name.
+ *
+ * @param tree The binary search tree to save.
+ * @param treeName The name to give the saved binary search tree.
+ */
+
+ fun saveTree(tree: BSTree, treeName: String) {
+ // Creates a new SQLController object and saves the binary search tree to the database with the given name.
+ val controller = SQLController()
+ controller.saveTree(tree, treeName)
+ }
+
+ /**
+ * Removes the node with the given value from the binary search tree and redraws the tree on the given pane.
+ *
+ * @param value The value of the node to remove.
+ * @param tree The binary search tree to remove the node from.
+ * @param treePane The pane to redraw the tree on.
+ */
+
+ fun deleteNode(value: Int, tree: BSTree, treePane: Pane) {
+ // Removes the node with the given value from the binary search tree.
+ tree.remove(value)
+ // Redraws the binary search tree on the given pane.
+ drawTree(tree, treePane)
+ }
+}
diff --git a/app/src/main/kotlin/app/controller/RBTController.kt b/app/src/main/kotlin/app/controller/RBTController.kt
new file mode 100644
index 0000000..2791662
--- /dev/null
+++ b/app/src/main/kotlin/app/controller/RBTController.kt
@@ -0,0 +1,200 @@
+package app.controller
+
+import bst.RedBlackTree
+import bst.db.controllers.Neo4jController
+import bst.nodes.RBTNode
+import javafx.collections.FXCollections
+import javafx.collections.ObservableList
+import javafx.scene.control.Tooltip
+import javafx.scene.layout.Pane
+import javafx.scene.layout.StackPane
+import javafx.scene.paint.Color
+import javafx.scene.shape.Circle
+import javafx.scene.shape.Line
+import javafx.scene.text.Text
+import javafx.scene.text.TextBoundsType
+import tornadofx.Controller
+import kotlin.math.min
+
+/**
+ * The RBTController class is responsible for managing red black trees.
+ *
+ * It extends the Controller class and provides additional functionality for working with RBT trees.
+ */
+
+class RBTController : Controller() {
+
+ /**
+ * Determines whether a given string can be parsed as an integer.
+ *
+ * @param s The string to check.
+ * @return True if the string can be parsed as an integer, false otherwise.
+ */
+
+ fun isNumeric(s: String): Boolean {
+ return try {
+ s.toInt()
+ true
+ } catch (e: NumberFormatException) {
+ false
+ }
+ }
+
+ /**
+ * Inserts a new node with the given key and value into the Red-Black Tree and redraws the tree.
+ * @param tree The Red-Black Tree to insert the node into.
+ * @param treePane The Pane to draw the updated tree on.
+ * @param key The key of the new node to insert.
+ * @param value The value of the new node to insert.
+ */
+
+ fun insertNode(tree: RedBlackTree, treePane: Pane, key: Int, value: String) {
+ tree.insert(key, value)
+ drawTree(tree, treePane)
+ }
+
+ /**
+ * Clears the Red-Black Tree and removes all nodes from the given Pane.
+ * @param tree The Red-Black Tree to clear.
+ * @param treePane The Pane to remove all nodes from.
+ */
+
+ fun clearTree(tree: RedBlackTree, treePane: Pane) {
+ tree.clear()
+ treePane.children.clear()
+ }
+
+ /**
+ * Draws the Red-Black Tree on the given Pane.
+ * @param tree The Red-Black Tree to draw.
+ * @param treePane The Pane to draw the tree on.
+ * @throws NullPointerException if the root of the tree is null.
+ */
+
+ fun drawTree(tree: RedBlackTree, treePane: Pane) {
+ treePane.children.clear()
+ val root = tree.getRoot()
+ if (root != null) {
+ drawNode(root, treePane, treePane.width / 2.0, treePane.width / 2.0, 250.0)
+ } else {
+ throw NullPointerException("Root of the tree is null.")
+ }
+ }
+
+ /**
+ * Draws a node of the Red-Black Tree on the given Pane, including a circle with the node's key and a tooltip with its value.
+ * If the node has a left child or a right child, it also draws a line to the child and recursively calls this function on the child.
+ * @param node The RBTNode to draw.
+ * @param treePane The Pane to draw the node on.
+ * @param x The x-coordinate of the center of the circle representing the node.
+ * @param y The y-coordinate of the center of the circle representing the node.
+ * @param offsetX The horizontal distance between the node and its child nodes.
+ */
+
+ private fun drawNode(node: RBTNode, treePane: Pane, x: Double, y: Double, offsetX: Double) {
+ // Create circle with node key
+ val circleRadius = 20.0
+ val circle = Circle(circleRadius)
+ circle.fill = if (node.color == RBTNode.Color.RED) Color.RED else Color.BLACK
+ circle.stroke = Color.BLACK
+
+ // Create text with node key
+ val nodeText = Text(node.key.toString())
+ nodeText.fill = if (circle.fill == Color.RED) Color.BLACK else Color.WHITE
+ nodeText.boundsType = TextBoundsType.VISUAL
+
+ // Scale text to fit inside circle
+ val scale = min(circleRadius * 1.3 / nodeText.boundsInLocal.width, circleRadius * 1.3 / nodeText.boundsInLocal.height)
+ nodeText.scaleX = scale
+ nodeText.scaleY = scale
+
+ // Create StackPane with circle and text, and set its position
+ val nodeStackPane = StackPane(circle, nodeText)
+ nodeStackPane.relocate(x - circleRadius, y - circleRadius)
+
+ // Add tooltip with node value to StackPane
+ val tooltip = Tooltip("value: ${node.value}")
+ Tooltip.install(nodeStackPane, tooltip)
+
+ // Add StackPane to treePane
+ treePane.children.add(nodeStackPane)
+
+ // Draw line to left child and recursively call drawNode on it
+ if (node.left != null) {
+ val leftX = x - offsetX
+ val leftY = y + 50
+ val leftLine = Line(x, y + circleRadius, leftX, leftY - circleRadius)
+ treePane.children.add(leftLine)
+ drawNode(node.left!!, treePane, leftX, leftY, offsetX / 2.0)
+ }
+
+ // Draw line to right child and recursively call drawNode on it
+ if (node.right != null) {
+ val rightX = x + offsetX
+ val rightY = y + 50
+ val rightLine = Line(x, y + circleRadius, rightX, rightY - circleRadius)
+ treePane.children.add(rightLine)
+ drawNode(node.right!!, treePane, rightX, rightY, offsetX / 2.0)
+ }
+ }
+
+ /**
+ * Gets a list of names of Red-Black Trees stored in a Neo4j database and returns it as an ObservableList of Strings.
+ * @return An ObservableList of Strings containing the names of Red-Black Trees stored in the Neo4j database.
+ */
+
+ fun getTreesList(): ObservableList? {
+ val controller = Neo4jController()
+ val treeNames = controller.getNames()
+ val values = FXCollections.observableArrayList()
+ treeNames.forEach {
+ values.add(it)
+ }
+ return values
+ }
+
+ /**
+ * Retrieves a Red-Black Tree with the given name from a Neo4j database and returns it.
+ * @param name The name of the Red-Black Tree to retrieve.
+ * @return The Red-Black Tree with the given name, or null if it does not exist in the database.
+ */
+
+ fun getTreeFromNeo4j(name: String): RedBlackTree? {
+ val controller = Neo4jController()
+ return controller.getTree(name)
+ }
+
+ /**
+ * Deletes a Red-Black Tree with the given name from a Neo4j database.
+ * @param name The name of the Red-Black Tree to delete.
+ */
+
+ fun deleteTreeFromDB(name: String) {
+ Neo4jController().run {
+ removeTree(name)
+ }
+ }
+
+ /**
+ * Saves a Red-Black Tree to a Neo4j database with the given name.
+ * @param tree The Red-Black Tree to save.
+ * @param treeName The name to give the Red-Black Tree in the database.
+ */
+
+ fun saveTree(tree: RedBlackTree, treeName: String) {
+ val controller = Neo4jController()
+ controller.saveTree(tree, treeName)
+ }
+
+ /**
+ * Removes a node with the given value from a Red-Black Tree, redraws the tree, and updates the given Pane.
+ * @param value The value of the node to remove.
+ * @param tree The Red-Black Tree to remove the node from.
+ * @param treePane The Pane to draw the updated tree on.
+ */
+
+ fun deleteNode(value: Int, tree: RedBlackTree, treePane: Pane) {
+ tree.remove(value)
+ drawTree(tree, treePane)
+ }
+}
diff --git a/app/src/main/kotlin/app/view/MainView.kt b/app/src/main/kotlin/app/view/MainView.kt
new file mode 100644
index 0000000..437c8d4
--- /dev/null
+++ b/app/src/main/kotlin/app/view/MainView.kt
@@ -0,0 +1,27 @@
+package app.view
+import app.view.treeView.BinarySearchTreeView
+import tornadofx.View
+import tornadofx.vbox
+
+/**
+ * Represents the main view of the application.
+ */
+
+class MainView : View() {
+
+ /**
+ * Represents the binary search tree view of the application.
+ */
+
+ private val tree: BinarySearchTreeView by inject()
+
+ /**
+ * Represents the root node of the view.
+ */
+
+ override val root = vbox {
+ primaryStage.minWidth = 400.0
+ primaryStage.minHeight = 600.0
+ add(tree)
+ }
+}
diff --git a/app/src/main/kotlin/app/view/treeView/AVLTreeView.kt b/app/src/main/kotlin/app/view/treeView/AVLTreeView.kt
new file mode 100644
index 0000000..9c0da18
--- /dev/null
+++ b/app/src/main/kotlin/app/view/treeView/AVLTreeView.kt
@@ -0,0 +1,168 @@
+package app.view.treeView
+
+import app.controller.AVLController
+import bst.AVLTree
+import javafx.beans.property.SimpleStringProperty
+import javafx.scene.control.Alert
+import javafx.scene.control.ScrollPane
+import javafx.scene.layout.Pane
+import tornadofx.ChangeListener
+import tornadofx.View
+import tornadofx.ViewTransition
+import tornadofx.action
+import tornadofx.alert
+import tornadofx.button
+import tornadofx.combobox
+import tornadofx.field
+import tornadofx.fieldset
+import tornadofx.form
+import tornadofx.hbox
+import tornadofx.scrollpane
+import tornadofx.seconds
+import tornadofx.textfield
+import tornadofx.vbox
+
+class AVLTreeView : View() {
+ private val controller: AVLController by inject()
+ private var tree = AVLTree()
+ private val treePane = Pane()
+ private val key = SimpleStringProperty()
+ private val value = SimpleStringProperty()
+ private var trees = controller.getTreesList()
+ private var selectedItem: String? = ""
+ private val treeName = SimpleStringProperty()
+ private val valueForDeletion = SimpleStringProperty()
+
+ init {
+ // Add listeners to the width and height properties of the scene
+ val sizeChangeListener = ChangeListener { _, _, _ ->
+ resizeTreePane()
+ }
+
+ primaryStage.widthProperty().addListener(sizeChangeListener)
+ primaryStage.heightProperty().addListener(sizeChangeListener)
+ }
+
+ private fun resizeTreePane() {
+ treePane.prefWidthProperty().bind(root.widthProperty())
+ treePane.prefHeightProperty().bind(root.heightProperty())
+ controller.drawTree(tree, treePane)
+ }
+
+ override val root = vbox {
+ hbox {
+ val availableTrees = combobox {
+ this@AVLTreeView.trees?.let { items.addAll(it) }
+ selectionModel.selectedItemProperty().addListener { _, _, newValue ->
+ this@AVLTreeView.selectedItem = newValue
+ }
+ }
+
+ button("Select") {
+ action {
+ println("Selected item: $selectedItem")
+ val loadedTree = selectedItem?.let { controller.getTreeFromJson(it) }
+ if (loadedTree != null) {
+ tree = loadedTree
+ controller.drawTree(tree, treePane)
+ }
+ }
+ }
+ button("Delete") {
+ action {
+ selectedItem?.let {
+ controller.clearTree(tree, treePane)
+ controller.deleteTreeFromDB(it)
+ }
+ availableTrees.items.remove(selectedItem)
+
+ println("Item deleted: $selectedItem")
+ }
+ }
+
+ button("Clear") {
+ action {
+ controller.clearTree(tree, treePane)
+ }
+ }
+ form {
+ fieldset {
+ field("Key") {
+ textfield(key)
+ }
+ field("Value") {
+ textfield(value)
+ }
+
+ button("Add") {
+ action {
+ if (key.value != null && value.value != null && controller.isNumeric(key.value)) {
+ controller.insertNode(tree, treePane, key.value.toInt(), value.value)
+ } else {
+ alert(type = Alert.AlertType.ERROR, header = "Insertion Error")
+ }
+ key.value = null
+ value.value = null
+ }
+ }
+ field("Key") {
+ textfield(valueForDeletion)
+ }
+ button("Delete") {
+ action {
+ if (controller.isNumeric(valueForDeletion.value)) {
+ controller.deleteNode(valueForDeletion.value.toInt(), tree, treePane)
+ } else {
+ alert(type = Alert.AlertType.ERROR, header = "Deletion Error")
+ }
+ }
+ }
+
+ field("Input tree name") {
+ textfield(treeName)
+ }
+ button("Save tree") {
+ action {
+ if (tree.getRoot() != null) {
+ controller.saveTree(tree, treeName.value)
+ if (!availableTrees.items.contains(treeName.value)) {
+ availableTrees.items.add(treeName.value)
+ }
+ } else {
+ alert(type = Alert.AlertType.ERROR, header = "Can not save tree with empty root")
+ }
+ }
+ }
+ }
+ }
+ }
+ button("Binary Search Tree") {
+ action {
+ replaceWith(
+ BinarySearchTreeView::class,
+ ViewTransition.Slide(0.3.seconds, ViewTransition.Direction.LEFT)
+ )
+ }
+ }
+ button("Red Black Tree") {
+ action {
+ replaceWith(RedBlackTreeView::class, ViewTransition.Slide(0.3.seconds, ViewTransition.Direction.LEFT))
+ }
+ }
+ scrollpane {
+ style = "-fx-background-color: transparent; -fx-border-color: transparent; -fx-focus-color: transparent;"
+ content = treePane
+ isPannable = true
+ hbarPolicy = ScrollPane.ScrollBarPolicy.NEVER
+ vbarPolicy = ScrollPane.ScrollBarPolicy.NEVER
+
+ hvalue = 0.5
+ vvalue = 0.5
+
+ treePane.apply {
+ minWidth = 5000.0
+ minHeight = 5000.0
+ }
+ }
+ }
+}
diff --git a/app/src/main/kotlin/app/view/treeView/BinarySearchTreeView.kt b/app/src/main/kotlin/app/view/treeView/BinarySearchTreeView.kt
new file mode 100644
index 0000000..a274d7f
--- /dev/null
+++ b/app/src/main/kotlin/app/view/treeView/BinarySearchTreeView.kt
@@ -0,0 +1,166 @@
+package app.view.treeView
+
+import app.controller.BSTController
+import bst.BSTree
+import javafx.beans.property.SimpleStringProperty
+import javafx.scene.control.Alert
+import javafx.scene.control.ScrollPane
+import javafx.scene.layout.Pane
+import tornadofx.ChangeListener
+import tornadofx.View
+import tornadofx.ViewTransition
+import tornadofx.action
+import tornadofx.alert
+import tornadofx.button
+import tornadofx.combobox
+import tornadofx.field
+import tornadofx.fieldset
+import tornadofx.form
+import tornadofx.hbox
+import tornadofx.scrollpane
+import tornadofx.seconds
+import tornadofx.textfield
+import tornadofx.vbox
+
+class BinarySearchTreeView : View() {
+ private val controller: BSTController by inject()
+ private var tree = BSTree()
+ private val treePane = Pane()
+ private val key = SimpleStringProperty()
+ private val value = SimpleStringProperty()
+ private var trees = controller.getTreesList()
+ private var selectedItem: String? = ""
+ private val treeName = SimpleStringProperty()
+ private val valueForDeletion = SimpleStringProperty()
+
+ init {
+ // Add listeners to the width and height properties of the scene
+ val sizeChangeListener = ChangeListener { _, _, _ ->
+ resizeTreePane()
+ }
+
+ primaryStage.widthProperty().addListener(sizeChangeListener)
+ primaryStage.heightProperty().addListener(sizeChangeListener)
+ }
+
+ private fun resizeTreePane() {
+ treePane.prefWidthProperty().bind(root.widthProperty())
+ treePane.prefHeightProperty().bind(root.heightProperty())
+ controller.drawTree(tree, treePane)
+ }
+
+ override val root = vbox {
+ hbox {
+ val availableTrees = combobox {
+ this@BinarySearchTreeView.trees?.let { items.addAll(it) }
+ selectionModel.selectedItemProperty().addListener { _, _, newValue ->
+ this@BinarySearchTreeView.selectedItem = newValue
+ }
+ }
+
+ button("Select") {
+ action {
+ println("Selected item: $selectedItem")
+ val loadedTree = selectedItem?.let { controller.getTreeFromDB(it) }
+ if (loadedTree != null) {
+ tree = loadedTree
+ controller.drawTree(tree, treePane)
+ }
+ }
+ }
+ button("Delete") {
+ action {
+ selectedItem?.let {
+ controller.clearTree(tree, treePane)
+ controller.deleteTreeFromDB(it)
+ }
+ availableTrees.items.remove(selectedItem)
+
+ println("Item deleted: $selectedItem")
+ }
+ }
+
+ button("Clear") {
+ action {
+ controller.clearTree(tree, treePane)
+ }
+ }
+ form {
+ fieldset {
+ field("Key") {
+ textfield(key)
+ }
+ field("Value") {
+ textfield(value)
+ }
+
+ button("Add") {
+ action {
+ if (key.value != null && value.value != null && controller.isNumeric(key.value)) {
+ controller.insertNode(tree, treePane, key.value.toInt(), value.value)
+ } else {
+ alert(type = Alert.AlertType.ERROR, header = "Insertion Error")
+ }
+ key.value = null
+ value.value = null
+ }
+ }
+ field("Key") {
+ textfield(valueForDeletion)
+ }
+ button("Delete") {
+ action {
+ if (controller.isNumeric(valueForDeletion.value)) {
+ controller.deleteNode(valueForDeletion.value.toInt(), tree, treePane)
+ } else {
+ alert(type = Alert.AlertType.ERROR, header = "Deletion Error")
+ }
+ }
+ }
+
+ field("Input tree name") {
+ textfield(treeName)
+ }
+ button("Save tree") {
+ action {
+ if (tree.getRoot() != null) {
+ // tree.treeName = treeName.value
+ controller.saveTree(tree, treeName.value)
+ if (!availableTrees.items.contains(treeName.value)) {
+ availableTrees.items.add(treeName.value)
+ }
+ } else {
+ alert(type = Alert.AlertType.ERROR, header = "Can not save tree with empty root")
+ }
+ }
+ }
+ }
+ }
+ }
+ button("AVL Tree") {
+ action {
+ replaceWith(AVLTreeView::class, ViewTransition.Slide(0.3.seconds, ViewTransition.Direction.LEFT))
+ }
+ }
+ button("Red Black Tree") {
+ action {
+ replaceWith(RedBlackTreeView::class, ViewTransition.Slide(0.3.seconds, ViewTransition.Direction.LEFT))
+ }
+ }
+ scrollpane {
+ style = "-fx-background-color: transparent; -fx-border-color: transparent; -fx-focus-color: transparent;"
+ content = treePane
+ isPannable = true
+ hbarPolicy = ScrollPane.ScrollBarPolicy.NEVER
+ vbarPolicy = ScrollPane.ScrollBarPolicy.NEVER
+
+ hvalue = 0.5
+ vvalue = 0.5
+
+ treePane.apply {
+ minWidth = 5000.0
+ minHeight = 5000.0
+ }
+ }
+ }
+}
diff --git a/app/src/main/kotlin/app/view/treeView/RedBlackTreeView.kt b/app/src/main/kotlin/app/view/treeView/RedBlackTreeView.kt
new file mode 100644
index 0000000..11283a2
--- /dev/null
+++ b/app/src/main/kotlin/app/view/treeView/RedBlackTreeView.kt
@@ -0,0 +1,166 @@
+package app.view.treeView
+
+import app.controller.RBTController
+import bst.RedBlackTree
+import javafx.beans.property.SimpleStringProperty
+import javafx.scene.control.Alert
+import javafx.scene.control.ScrollPane
+import javafx.scene.layout.Pane
+import tornadofx.ChangeListener
+import tornadofx.View
+import tornadofx.ViewTransition
+import tornadofx.action
+import tornadofx.alert
+import tornadofx.button
+import tornadofx.combobox
+import tornadofx.field
+import tornadofx.fieldset
+import tornadofx.form
+import tornadofx.hbox
+import tornadofx.scrollpane
+import tornadofx.seconds
+import tornadofx.textfield
+import tornadofx.vbox
+
+class RedBlackTreeView : View() {
+ private val controller: RBTController by inject()
+ private var tree = RedBlackTree()
+ private val treePane = Pane()
+ private val key = SimpleStringProperty()
+ private val value = SimpleStringProperty()
+ private var trees = controller.getTreesList()
+ private var selectedItem: String? = ""
+ private val treeName = SimpleStringProperty()
+ private val valueForDeletion = SimpleStringProperty()
+
+ init {
+ val sizeChangeListener = ChangeListener { _, _, _ ->
+ resizeTreePane()
+ }
+
+ primaryStage.widthProperty().addListener(sizeChangeListener)
+ primaryStage.heightProperty().addListener(sizeChangeListener)
+ }
+
+ private fun resizeTreePane() {
+ treePane.prefWidthProperty().bind(root.widthProperty())
+ treePane.prefHeightProperty().bind(root.heightProperty())
+ controller.drawTree(tree, treePane)
+ }
+
+ override val root = vbox {
+ hbox {
+ val availableTrees = combobox {
+ this@RedBlackTreeView.trees?.let { items.addAll(it) }
+ selectionModel.selectedItemProperty().addListener { _, _, newValue ->
+ this@RedBlackTreeView.selectedItem = newValue
+ }
+ }
+
+ button("Select") {
+ action {
+ println("Selected item: $selectedItem")
+ val loadedTree = selectedItem?.let { controller.getTreeFromNeo4j(it) }
+ if (loadedTree != null) {
+ tree = loadedTree
+ controller.drawTree(tree, treePane)
+ }
+ }
+ }
+ button("Delete") {
+ action {
+ selectedItem?.let {
+ controller.clearTree(tree, treePane)
+ controller.deleteTreeFromDB(it)
+ }
+ availableTrees.items.remove(selectedItem)
+
+ println("Item deleted: $selectedItem")
+ }
+ }
+
+ button("Clear") {
+ action {
+ controller.clearTree(tree, treePane)
+ }
+ }
+ form {
+ fieldset {
+ field("Key") {
+ textfield(key)
+ }
+ field("Value") {
+ textfield(value)
+ }
+
+ button("Add") {
+ action {
+ if (key.value != null && value.value != null && controller.isNumeric(key.value)) {
+ controller.insertNode(tree, treePane, key.value.toInt(), value.value)
+ } else {
+ alert(type = Alert.AlertType.ERROR, header = "Insertion Error")
+ }
+ key.value = null
+ value.value = null
+ }
+ }
+ field("Value") {
+ textfield(valueForDeletion)
+ }
+ button("Delete") {
+ action {
+ if (controller.isNumeric(valueForDeletion.value)) {
+ controller.deleteNode(valueForDeletion.value.toInt(), tree, treePane)
+ } else {
+ alert(type = Alert.AlertType.ERROR, header = "Deletion Error")
+ }
+ }
+ }
+
+ field("Input tree name") {
+ textfield(treeName)
+ }
+ button("Save tree") {
+ action {
+ if (tree.getRoot() != null) {
+// tree.treeName = treeName.value
+ controller.saveTree(tree, treeName.value)
+ if (!availableTrees.items.contains(treeName.value)) {
+ availableTrees.items.add(treeName.value)
+ }
+ } else {
+ alert(type = Alert.AlertType.ERROR, header = "Can not save tree with empty root")
+ }
+ }
+ }
+ }
+ }
+ }
+ button("AVL Tree") {
+ action {
+ replaceWith(AVLTreeView::class, ViewTransition.Slide(0.3.seconds, ViewTransition.Direction.LEFT))
+ }
+ }
+
+ button("Binary Search Tree") {
+ action {
+ replaceWith(BinarySearchTreeView::class, ViewTransition.Slide(0.3.seconds, ViewTransition.Direction.LEFT))
+ }
+ }
+ scrollpane {
+ style = "-fx-background-color: transparent; -fx-border-color: transparent; -fx-focus-color: transparent;"
+ content = treePane
+ isPannable = true
+ hbarPolicy = ScrollPane.ScrollBarPolicy.NEVER
+ vbarPolicy = ScrollPane.ScrollBarPolicy.NEVER
+
+ hvalue = 0.5
+ vvalue = 0.5
+
+ treePane.apply {
+ minWidth = 5000.0
+ minHeight = 5000.0
+ }
+ }
+ }
+}
diff --git a/docker-compose.yml b/docker-compose.yml
new file mode 100644
index 0000000..1bd5c58
--- /dev/null
+++ b/docker-compose.yml
@@ -0,0 +1,24 @@
+version: "3"
+services:
+ local-database:
+ image: postgres:15.2
+ env_file:
+ - postgres.env
+ ports:
+ - "5432:5432"
+ volumes:
+ - pg-volume:/var/lib/postgresql/data
+ neo4j:
+ image: neo4j:5.6.0
+ container_name: neo4j
+ env_file:
+ - neo4j.env
+ ports:
+ - "7474:7474"
+ - "7687:7687"
+ volumes:
+ - neo4j-volume:/data
+ - neo4j-volume:/logs
+volumes:
+ pg-volume: {}
+ neo4j-volume: {}
diff --git a/gradle/wrapper/gradle-wrapper.jar b/gradle/wrapper/gradle-wrapper.jar
new file mode 100644
index 0000000..ccebba7
Binary files /dev/null and b/gradle/wrapper/gradle-wrapper.jar differ
diff --git a/gradle/wrapper/gradle-wrapper.properties b/gradle/wrapper/gradle-wrapper.properties
new file mode 100644
index 0000000..bdc9a83
--- /dev/null
+++ b/gradle/wrapper/gradle-wrapper.properties
@@ -0,0 +1,6 @@
+distributionBase=GRADLE_USER_HOME
+distributionPath=wrapper/dists
+distributionUrl=https\://services.gradle.org/distributions/gradle-8.0.2-bin.zip
+networkTimeout=10000
+zipStoreBase=GRADLE_USER_HOME
+zipStorePath=wrapper/dists
diff --git a/gradlew b/gradlew
new file mode 100755
index 0000000..79a61d4
--- /dev/null
+++ b/gradlew
@@ -0,0 +1,244 @@
+#!/bin/sh
+
+#
+# Copyright © 2015-2021 the original authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# https://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+
+##############################################################################
+#
+# Gradle start up script for POSIX generated by Gradle.
+#
+# Important for running:
+#
+# (1) You need a POSIX-compliant shell to run this script. If your /bin/sh is
+# noncompliant, but you have some other compliant shell such as ksh or
+# bash, then to run this script, type that shell name before the whole
+# command line, like:
+#
+# ksh Gradle
+#
+# Busybox and similar reduced shells will NOT work, because this script
+# requires all of these POSIX shell features:
+# * functions;
+# * expansions «$var», «${var}», «${var:-default}», «${var+SET}»,
+# «${var#prefix}», «${var%suffix}», and «$( cmd )»;
+# * compound commands having a testable exit status, especially «case»;
+# * various built-in commands including «command», «set», and «ulimit».
+#
+# Important for patching:
+#
+# (2) This script targets any POSIX shell, so it avoids extensions provided
+# by Bash, Ksh, etc; in particular arrays are avoided.
+#
+# The "traditional" practice of packing multiple parameters into a
+# space-separated string is a well documented source of bugs and security
+# problems, so this is (mostly) avoided, by progressively accumulating
+# options in "$@", and eventually passing that to Java.
+#
+# Where the inherited environment variables (DEFAULT_JVM_OPTS, JAVA_OPTS,
+# and GRADLE_OPTS) rely on word-splitting, this is performed explicitly;
+# see the in-line comments for details.
+#
+# There are tweaks for specific operating systems such as AIX, CygWin,
+# Darwin, MinGW, and NonStop.
+#
+# (3) This script is generated from the Groovy template
+# https://github.com/gradle/gradle/blob/HEAD/subprojects/plugins/src/main/resources/org/gradle/api/internal/plugins/unixStartScript.txt
+# within the Gradle project.
+#
+# You can find Gradle at https://github.com/gradle/gradle/.
+#
+##############################################################################
+
+# Attempt to set APP_HOME
+
+# Resolve links: $0 may be a link
+app_path=$0
+
+# Need this for daisy-chained symlinks.
+while
+ APP_HOME=${app_path%"${app_path##*/}"} # leaves a trailing /; empty if no leading path
+ [ -h "$app_path" ]
+do
+ ls=$( ls -ld "$app_path" )
+ link=${ls#*' -> '}
+ case $link in #(
+ /*) app_path=$link ;; #(
+ *) app_path=$APP_HOME$link ;;
+ esac
+done
+
+# This is normally unused
+# shellcheck disable=SC2034
+APP_BASE_NAME=${0##*/}
+APP_HOME=$( cd "${APP_HOME:-./}" && pwd -P ) || exit
+
+# Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+DEFAULT_JVM_OPTS='"-Xmx64m" "-Xms64m"'
+
+# Use the maximum available, or set MAX_FD != -1 to use that value.
+MAX_FD=maximum
+
+warn () {
+ echo "$*"
+} >&2
+
+die () {
+ echo
+ echo "$*"
+ echo
+ exit 1
+} >&2
+
+# OS specific support (must be 'true' or 'false').
+cygwin=false
+msys=false
+darwin=false
+nonstop=false
+case "$( uname )" in #(
+ CYGWIN* ) cygwin=true ;; #(
+ Darwin* ) darwin=true ;; #(
+ MSYS* | MINGW* ) msys=true ;; #(
+ NONSTOP* ) nonstop=true ;;
+esac
+
+CLASSPATH=$APP_HOME/gradle/wrapper/gradle-wrapper.jar
+
+
+# Determine the Java command to use to start the JVM.
+if [ -n "$JAVA_HOME" ] ; then
+ if [ -x "$JAVA_HOME/jre/sh/java" ] ; then
+ # IBM's JDK on AIX uses strange locations for the executables
+ JAVACMD=$JAVA_HOME/jre/sh/java
+ else
+ JAVACMD=$JAVA_HOME/bin/java
+ fi
+ if [ ! -x "$JAVACMD" ] ; then
+ die "ERROR: JAVA_HOME is set to an invalid directory: $JAVA_HOME
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+ fi
+else
+ JAVACMD=java
+ which java >/dev/null 2>&1 || die "ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+fi
+
+# Increase the maximum file descriptors if we can.
+if ! "$cygwin" && ! "$darwin" && ! "$nonstop" ; then
+ case $MAX_FD in #(
+ max*)
+ # In POSIX sh, ulimit -H is undefined. That's why the result is checked to see if it worked.
+ # shellcheck disable=SC3045
+ MAX_FD=$( ulimit -H -n ) ||
+ warn "Could not query maximum file descriptor limit"
+ esac
+ case $MAX_FD in #(
+ '' | soft) :;; #(
+ *)
+ # In POSIX sh, ulimit -n is undefined. That's why the result is checked to see if it worked.
+ # shellcheck disable=SC3045
+ ulimit -n "$MAX_FD" ||
+ warn "Could not set maximum file descriptor limit to $MAX_FD"
+ esac
+fi
+
+# Collect all arguments for the java command, stacking in reverse order:
+# * args from the command line
+# * the main class name
+# * -classpath
+# * -D...appname settings
+# * --module-path (only if needed)
+# * DEFAULT_JVM_OPTS, JAVA_OPTS, and GRADLE_OPTS environment variables.
+
+# For Cygwin or MSYS, switch paths to Windows format before running java
+if "$cygwin" || "$msys" ; then
+ APP_HOME=$( cygpath --path --mixed "$APP_HOME" )
+ CLASSPATH=$( cygpath --path --mixed "$CLASSPATH" )
+
+ JAVACMD=$( cygpath --unix "$JAVACMD" )
+
+ # Now convert the arguments - kludge to limit ourselves to /bin/sh
+ for arg do
+ if
+ case $arg in #(
+ -*) false ;; # don't mess with options #(
+ /?*) t=${arg#/} t=/${t%%/*} # looks like a POSIX filepath
+ [ -e "$t" ] ;; #(
+ *) false ;;
+ esac
+ then
+ arg=$( cygpath --path --ignore --mixed "$arg" )
+ fi
+ # Roll the args list around exactly as many times as the number of
+ # args, so each arg winds up back in the position where it started, but
+ # possibly modified.
+ #
+ # NB: a `for` loop captures its iteration list before it begins, so
+ # changing the positional parameters here affects neither the number of
+ # iterations, nor the values presented in `arg`.
+ shift # remove old arg
+ set -- "$@" "$arg" # push replacement arg
+ done
+fi
+
+# Collect all arguments for the java command;
+# * $DEFAULT_JVM_OPTS, $JAVA_OPTS, and $GRADLE_OPTS can contain fragments of
+# shell script including quotes and variable substitutions, so put them in
+# double quotes to make sure that they get re-expanded; and
+# * put everything else in single quotes, so that it's not re-expanded.
+
+set -- \
+ "-Dorg.gradle.appname=$APP_BASE_NAME" \
+ -classpath "$CLASSPATH" \
+ org.gradle.wrapper.GradleWrapperMain \
+ "$@"
+
+# Stop when "xargs" is not available.
+if ! command -v xargs >/dev/null 2>&1
+then
+ die "xargs is not available"
+fi
+
+# Use "xargs" to parse quoted args.
+#
+# With -n1 it outputs one arg per line, with the quotes and backslashes removed.
+#
+# In Bash we could simply go:
+#
+# readarray ARGS < <( xargs -n1 <<<"$var" ) &&
+# set -- "${ARGS[@]}" "$@"
+#
+# but POSIX shell has neither arrays nor command substitution, so instead we
+# post-process each arg (as a line of input to sed) to backslash-escape any
+# character that might be a shell metacharacter, then use eval to reverse
+# that process (while maintaining the separation between arguments), and wrap
+# the whole thing up as a single "set" statement.
+#
+# This will of course break if any of these variables contains a newline or
+# an unmatched quote.
+#
+
+eval "set -- $(
+ printf '%s\n' "$DEFAULT_JVM_OPTS $JAVA_OPTS $GRADLE_OPTS" |
+ xargs -n1 |
+ sed ' s~[^-[:alnum:]+,./:=@_]~\\&~g; ' |
+ tr '\n' ' '
+ )" '"$@"'
+
+exec "$JAVACMD" "$@"
diff --git a/gradlew.bat b/gradlew.bat
new file mode 100644
index 0000000..93e3f59
--- /dev/null
+++ b/gradlew.bat
@@ -0,0 +1,92 @@
+@rem
+@rem Copyright 2015 the original author or authors.
+@rem
+@rem Licensed under the Apache License, Version 2.0 (the "License");
+@rem you may not use this file except in compliance with the License.
+@rem You may obtain a copy of the License at
+@rem
+@rem https://www.apache.org/licenses/LICENSE-2.0
+@rem
+@rem Unless required by applicable law or agreed to in writing, software
+@rem distributed under the License is distributed on an "AS IS" BASIS,
+@rem WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+@rem See the License for the specific language governing permissions and
+@rem limitations under the License.
+@rem
+
+@if "%DEBUG%"=="" @echo off
+@rem ##########################################################################
+@rem
+@rem Gradle startup script for Windows
+@rem
+@rem ##########################################################################
+
+@rem Set local scope for the variables with windows NT shell
+if "%OS%"=="Windows_NT" setlocal
+
+set DIRNAME=%~dp0
+if "%DIRNAME%"=="" set DIRNAME=.
+@rem This is normally unused
+set APP_BASE_NAME=%~n0
+set APP_HOME=%DIRNAME%
+
+@rem Resolve any "." and ".." in APP_HOME to make it shorter.
+for %%i in ("%APP_HOME%") do set APP_HOME=%%~fi
+
+@rem Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+set DEFAULT_JVM_OPTS="-Xmx64m" "-Xms64m"
+
+@rem Find java.exe
+if defined JAVA_HOME goto findJavaFromJavaHome
+
+set JAVA_EXE=java.exe
+%JAVA_EXE% -version >NUL 2>&1
+if %ERRORLEVEL% equ 0 goto execute
+
+echo.
+echo ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+echo.
+echo Please set the JAVA_HOME variable in your environment to match the
+echo location of your Java installation.
+
+goto fail
+
+:findJavaFromJavaHome
+set JAVA_HOME=%JAVA_HOME:"=%
+set JAVA_EXE=%JAVA_HOME%/bin/java.exe
+
+if exist "%JAVA_EXE%" goto execute
+
+echo.
+echo ERROR: JAVA_HOME is set to an invalid directory: %JAVA_HOME%
+echo.
+echo Please set the JAVA_HOME variable in your environment to match the
+echo location of your Java installation.
+
+goto fail
+
+:execute
+@rem Setup the command line
+
+set CLASSPATH=%APP_HOME%\gradle\wrapper\gradle-wrapper.jar
+
+
+@rem Execute Gradle
+"%JAVA_EXE%" %DEFAULT_JVM_OPTS% %JAVA_OPTS% %GRADLE_OPTS% "-Dorg.gradle.appname=%APP_BASE_NAME%" -classpath "%CLASSPATH%" org.gradle.wrapper.GradleWrapperMain %*
+
+:end
+@rem End local scope for the variables with windows NT shell
+if %ERRORLEVEL% equ 0 goto mainEnd
+
+:fail
+rem Set variable GRADLE_EXIT_CONSOLE if you need the _script_ return code instead of
+rem the _cmd.exe /c_ return code!
+set EXIT_CODE=%ERRORLEVEL%
+if %EXIT_CODE% equ 0 set EXIT_CODE=1
+if not ""=="%GRADLE_EXIT_CONSOLE%" exit %EXIT_CODE%
+exit /b %EXIT_CODE%
+
+:mainEnd
+if "%OS%"=="Windows_NT" endlocal
+
+:omega
diff --git a/json/test.json b/json/test.json
new file mode 100644
index 0000000..3445cd5
--- /dev/null
+++ b/json/test.json
@@ -0,0 +1 @@
+{"treeName":"","rootNode":{"height":2,"key":234,"value":"gfh","left":{"height":1,"key":23,"value":"","right":{"height":0,"key":67,"value":"dgfh"}},"right":{"height":0,"key":324,"value":"fdsg"}}}
\ No newline at end of file
diff --git a/neo4j.env b/neo4j.env
new file mode 100644
index 0000000..c3e61fd
--- /dev/null
+++ b/neo4j.env
@@ -0,0 +1 @@
+NEO4J_AUTH=neo4j/password
\ No newline at end of file
diff --git a/postgres.env b/postgres.env
new file mode 100644
index 0000000..ff9a750
--- /dev/null
+++ b/postgres.env
@@ -0,0 +1,3 @@
+POSTGRES_USER=test
+POSTGRES_PASSWORD=test-test
+POSTGRES_DB=test
\ No newline at end of file
diff --git a/readme_gif/example1.gif b/readme_gif/example1.gif
new file mode 100644
index 0000000..4825c9a
Binary files /dev/null and b/readme_gif/example1.gif differ
diff --git a/settings.gradle.kts b/settings.gradle.kts
new file mode 100644
index 0000000..f368ad1
--- /dev/null
+++ b/settings.gradle.kts
@@ -0,0 +1,3 @@
+rootProject.name = "trees-3"
+include("app")
+include("trees")
diff --git a/start-db.bat b/start-db.bat
new file mode 100644
index 0000000..43793b2
--- /dev/null
+++ b/start-db.bat
@@ -0,0 +1,3 @@
+@echo off
+set BASEDIR=%~dp0
+docker-compose --file "%BASEDIR%docker-compose.yml" up
diff --git a/start-db.sh b/start-db.sh
new file mode 100755
index 0000000..e3a97f1
--- /dev/null
+++ b/start-db.sh
@@ -0,0 +1,4 @@
+#!/usr/bin/env bash
+set -e
+BASEDIR=$(dirname "$0")
+docker-compose --file "${BASEDIR}"/docker-compose.yml up
diff --git a/trees/build.gradle.kts b/trees/build.gradle.kts
new file mode 100644
index 0000000..a1cbaf8
--- /dev/null
+++ b/trees/build.gradle.kts
@@ -0,0 +1,61 @@
+plugins {
+ // Apply the org.jetbrains.kotlin.jvm Plugin to add support for Kotlin.
+ id("org.jetbrains.kotlin.jvm") version "1.8.10"
+ id("jacoco")
+ id("org.jetbrains.kotlin.plugin.noarg") version "1.8.20"
+ id("org.jetbrains.kotlin.plugin.serialization") version "1.8.10"
+}
+
+repositories {
+ // Use Maven Central for resolving dependencies.
+ mavenCentral()
+}
+
+dependencies {
+ // Use the Kotlin JUnit 5 integration.
+ testImplementation("org.jetbrains.kotlin:kotlin-test-junit5")
+
+ // Use the JUnit 5 integration.
+ testImplementation("org.junit.jupiter:junit-jupiter-engine:5.9.2")
+
+ implementation("io.github.microutils:kotlin-logging-jvm:2.0.11")
+
+ implementation("org.slf4j", "slf4j-simple", "2.0.0")
+
+ implementation("org.neo4j:neo4j-ogm-core:4.0.5")
+ runtimeOnly("org.neo4j:neo4j-ogm-bolt-driver:4.0.5")
+
+ implementation("com.google.code.gson:gson:2.10.1")
+
+ // Use JetBrains Exposed
+ implementation("org.jetbrains.exposed:exposed-core:0.40.1")
+ implementation("org.jetbrains.exposed:exposed-dao:0.40.1")
+ implementation("org.jetbrains.exposed:exposed-jdbc:0.40.1")
+
+ implementation("org.xerial:sqlite-jdbc:3.41.2.1")
+
+ implementation("org.jetbrains.kotlinx:kotlinx-serialization-json:1.5.0")
+ implementation("org.postgresql:postgresql:42.5.4")
+}
+
+tasks.test {
+ // Use JUnit Platform for unit tests.
+ finalizedBy(tasks.jacocoTestReport) // report is always generated after tests run
+ useJUnitPlatform()
+}
+
+tasks.jacocoTestReport {
+ dependsOn(tasks.test) // tests are required to run before generating the report
+ reports {
+ xml.required.set(false)
+ html.required.set(true)
+ html.outputLocation.set(layout.buildDirectory.dir("reports/jacoco"))
+ csv.required.set(true)
+ csv.outputLocation.set(layout.buildDirectory.file("jacoco/report.csv"))
+ }
+}
+
+noArg {
+ annotation("org.neo4j.ogm.annotation.NodeEntity")
+ annotation("org.neo4j.ogm.annotation.RelationshipEntity")
+}
diff --git a/trees/src/main/kotlin/bst/AVLTree.kt b/trees/src/main/kotlin/bst/AVLTree.kt
new file mode 100644
index 0000000..4a3f512
--- /dev/null
+++ b/trees/src/main/kotlin/bst/AVLTree.kt
@@ -0,0 +1,173 @@
+package bst
+
+import bst.nodes.AVLNode
+import kotlin.math.max
+
+/**
+ * This class represents an AVL tree data structure and extends the BalancingTree class.
+ * @param the type of keys in the AVL tree, must implement Comparable interface.
+ * @param the type of values in the AVL tree.
+ */
+class AVLTree, V>(@Transient val key: K? = null, @Transient val value: V? = null) :
+ BalancingTree>() {
+
+ /**
+ * Initializes a new AVL node with the given key and value.
+ * @param key the key of the node.
+ * @param value the value of the node.
+ * @return a new AVL node with the given key and value.
+ */
+ override fun initNode(key: K, value: V): AVLNode = AVLNode(key, value)
+
+ /**
+ * Initializes an AVL tree with a root node if the key and value are not null.
+ * @param key the key of the root node.
+ * @param value the value of the root node.
+ */
+ init {
+ if (key != null && value != null) {
+ rootNode = initNode(key, value)
+ }
+ }
+
+ /**
+ * Inserts a new node with the given key and value into the AVL tree.
+ * @param node the current AVL node being examined, can be null.
+ * @param key the key of the new node to be inserted.
+ * @param value the value of the new node to be inserted.
+ * @return the AVL node that is the root of the subtree after insertion and rebalancing.
+ */
+ override fun insertNode(node: AVLNode?, key: K, value: V): AVLNode {
+ if (node == null) return initNode(key, value)
+ if (key < node.key) {
+ node.left = insertNode(node.left, key, value)
+ } else if (key > node.key) {
+ node.right = insertNode(node.right, key, value)
+ } else {
+ node.value = value
+ }
+ updateHeight(node)
+ return balance(node)
+ }
+
+ /**
+ * Gets the height of the given AVL node.
+ * @param node the AVL node whose height is to be returned, can be null.
+ * @return the height of the AVL node if it is not null, -1 otherwise.
+ */
+ private fun getHeight(node: AVLNode?): Int {
+ return node?.height ?: -1
+ }
+
+ /**
+ * Updates the height of the given AVL node based on the heights of its left and right subtrees.
+ * @param node the AVL node whose height is to be updated.
+ */
+ private fun updateHeight(node: AVLNode) {
+ node.height = max(getHeight(node.left), getHeight(node.right)) + 1
+ }
+
+ /**
+ * Gets the balance factor of the given AVL node.
+ * @param node the AVL node whose balance factor is to be returned, can be null.
+ * @return the balance factor of the AVL node if it is not null, 0 otherwise.
+ */
+ private fun getBalanceFactor(node: AVLNode?): Int = when (node) {
+ null -> 0
+ else -> getHeight(node.right) - getHeight(node.left)
+ }
+
+ /**
+ * Balances the given AVL node by performing rotations if necessary.
+ * @param node the AVL node to be balanced.
+ * @return the AVL node that is the root of the subtree after balancing.
+ */
+ private fun balance(node: AVLNode): AVLNode {
+ return when (getBalanceFactor(node)) {
+ -2 -> {
+ if (getBalanceFactor(node.left) == 1) {
+ node.left = node.left?.let { rotateLeft(it) }
+ }
+ return rotateRight(node)
+ }
+
+ 2 -> {
+ if (getBalanceFactor(node.right) == -1) {
+ node.right = node.right?.let { rotateRight(it) }
+ }
+ return rotateLeft(node)
+ }
+
+ else -> node
+ }
+ }
+
+ /**
+ * Removes a node with the given key from the AVL tree starting at the given node.
+ *
+ * @param node The root node of the AVL tree or a subtree.
+ * @param key The key of the node to be removed.
+ * @return The root node of the AVL tree or a subtree after the removal.
+ */
+ override fun removeNode(node: AVLNode?, key: K): AVLNode? {
+ if (node == null) return null
+ if (key < node.key) {
+ node.left = removeNode(node.left, key)
+ } else if (key > node.key) {
+ node.right = removeNode(node.right, key)
+ } else {
+ if (node.left == null) {
+ return node.right
+ } else if (node.right == null) {
+ return node.left
+ } else {
+ // Find the maximum node in the left subtree
+ val tmp: AVLNode =
+ findMax(node.left) ?: throw IllegalStateException("Left subtree must contain elements")
+ // Replace the node to be removed with the maximum node in the left subtree
+ node.key = tmp.key
+ node.value = tmp.value
+ // Remove the maximum node in the left subtree
+ node.left = removeNode(node.left, tmp.key)
+ }
+ }
+ // Update the height of the node after the removal
+ updateHeight(node)
+ // Balance the node after the removal
+ return balance(node)
+ }
+
+ /**
+ * Rotates the given AVL node to the right.
+ *
+ * @param node The AVL node to be rotated.
+ * @return The AVL node that has been rotated.
+ * @throws IllegalStateException If the node's left child is null.
+ */
+ override fun rotateRight(node: AVLNode): AVLNode {
+ val left = node.left ?: throw IllegalStateException("Node's left child cannot be null")
+ node.left = left.right
+ left.right = node
+ // Update the height of the nodes after the rotation
+ updateHeight(node)
+ updateHeight(left)
+ return left
+ }
+
+ /**
+ * Rotates the given AVL node to the left.
+ *
+ * @param node The AVL node to be rotated.
+ * @return The AVL node that has been rotated.
+ * @throws IllegalStateException If the node's right child is null.
+ */
+ override fun rotateLeft(node: AVLNode): AVLNode {
+ val right = node.right ?: throw IllegalStateException("Node's right child cannot be null")
+ node.right = right.left
+ right.left = node
+ // Update the height of the nodes after the rotation
+ updateHeight(node)
+ updateHeight(right)
+ return right
+ }
+}
diff --git a/trees/src/main/kotlin/bst/AbstractBST.kt b/trees/src/main/kotlin/bst/AbstractBST.kt
new file mode 100644
index 0000000..551d3b8
--- /dev/null
+++ b/trees/src/main/kotlin/bst/AbstractBST.kt
@@ -0,0 +1,169 @@
+package bst
+
+import bst.nodes.BinaryNode
+
+/**
+ * An abstract class representing a binary search tree data structure.
+ *
+ * @param K the type of keys maintained by this binary search tree.
+ * @param V the type of mapped values.
+ * @param Self the type of the binary nodes in this binary search tree.
+ */
+
+abstract class AbstractBST, V, Self : BinaryNode> : Tree {
+
+ /**
+ * The name of this binary search tree.
+ */
+
+ var treeName: String = ""
+
+ /**
+ * The root node of this binary search tree.
+ */
+
+ internal var rootNode: Self? = null
+
+ /**
+ * Sets the name of this binary search tree.
+ * @param treeName the name of this binary search tree.
+ */
+
+ fun setName(treeName: String) {
+ this.treeName = treeName
+ }
+
+ /**
+ * Returns the root node of this binary search tree.
+ *
+ * @return the root node of this binary search tree.
+ */
+
+ fun getRoot(): Self? = this.rootNode
+
+ /**
+ * Clears this binary search tree by setting its root node to null.
+ */
+
+ fun clear() {
+ this.rootNode = null
+ }
+
+ /**
+ * Initializes a new binary node with the given key and value\.
+ * @param key the key of the new node\.
+ * @param value the value of the new node\.
+ * @return a new binary node with the given key and value\.
+ */
+
+ protected abstract fun initNode(key: K, value: V): Self
+
+ /**
+ * Inserts a new node with the given key and value into this binary search tree\.
+ * @param key the key of the new node\.
+ * @param value the value of the new node\.
+ */
+
+ override fun insert(key: K, value: V) {
+ rootNode = insertNode(rootNode, key, value)
+ }
+
+ /**
+ * Inserts a new node with the given key and value into the binary search tree rooted at the given node\.
+ *
+ * @param node the root node of the binary search tree to insert the new node into\.
+ * @param key the key of the new node\.
+ * @param value the value of the new node\.
+ * @return the root node of the binary search tree after the new node has been inserted\.
+ */
+
+ protected open fun insertNode(node: Self?, key: K, value: V): Self {
+ if (node == null) return initNode(key, value)
+ if (key < node.key) {
+ node.left = insertNode(node.left, key, value)
+ } else if (key > node.key) {
+ node.right = insertNode(node.right, key, value)
+ } else {
+ node.value = value
+ }
+ return node
+ }
+
+ /**
+ * Removes the node with the given key from the tree.
+ * @param key the key of the node to remove
+ */
+
+ override fun remove(key: K) {
+ rootNode = removeNode(rootNode, key)
+ }
+
+ /**
+ * Recursively removes the node with the given key from the subtree rooted at the given node.
+ * @param node the root of the subtree to remove the node from
+ * @param key the key of the node to remove
+ * @return the root of the updated subtree
+ */
+
+ protected open fun removeNode(node: Self?, key: K): Self? {
+ if (node == null) return null
+ if (key < node.key) {
+ node.left = removeNode(node.left, key)
+ } else if (key > node.key) {
+ node.right = removeNode(node.right, key)
+ } else {
+ if (node.left == null) {
+ return node.right
+ } else if (node.right == null) {
+ return node.left
+ } else {
+ val tmp: Self = findMax(node.left)!!
+ node.key = tmp.key
+ node.value = tmp.value
+ node.left = removeNode(node.left, tmp.key)
+ }
+ }
+ return node
+ }
+
+ /**
+ * Finds the value associated with the given key in the tree.
+ * @param key the key to search for in the tree
+ * @return the value associated with the given key if it exists, otherwise null
+ */
+
+ override fun find(key: K): V? = findNode(rootNode, key)
+
+ /**
+ * Recursively searches for the value associated with the given key in the subtree rooted at the given node.
+ * @param node the root of the subtree to search in
+ * @param key the key to search for in the subtree
+ * @return the value associated with the given key if it exists in the subtree, otherwise null
+ */
+
+ private fun findNode(node: Self?, key: K): V? {
+ return if (node == null) {
+ null
+ } else if (key == node.key) {
+ node.value
+ } else {
+ if (key < node.key) {
+ findNode(node.left, key)
+ } else {
+ findNode(node.right, key)
+ }
+ }
+ }
+
+ /**
+ * Recursively finds the node with the maximum key in the subtree rooted at the given node.
+ * @param node the root of the subtree to search in
+ * @return the node with the maximum key in the subtree, or null if the subtree is empty
+ */
+
+ protected fun findMax(node: Self?): Self? = when {
+ node == null -> null
+ node.right == null -> node
+ else -> findMax(node.right)
+ }
+}
diff --git a/trees/src/main/kotlin/bst/BSTree.kt b/trees/src/main/kotlin/bst/BSTree.kt
new file mode 100644
index 0000000..b2b07a9
--- /dev/null
+++ b/trees/src/main/kotlin/bst/BSTree.kt
@@ -0,0 +1,35 @@
+package bst
+
+import bst.nodes.BSTNode
+
+/**
+ * A binary search tree implementation using a linked structure.
+ * @param K the type of keys stored in the tree, must implement Comparable
+ * @param V the type of values stored in the tree
+ * @param Self the type of the nodes in the tree, must extend BSTNode
+ */
+
+class BSTree, V>(val key: K? = null, val value: V? = null) :
+ AbstractBST>() {
+
+ /**
+ * Initializes a new node with the given key and value.
+ * @param key the key of the new node
+ * @param value the value of the new node
+ * @return the new node
+ */
+
+ override fun initNode(key: K, value: V): BSTNode = BSTNode(key, value)
+
+ /**
+ * Constructs a new BSTree with the given key and value as the root node.
+ * @param key the key of the root node
+ * @param value the value of the root node
+ */
+
+ init {
+ if (key != null && value != null) {
+ rootNode = initNode(key, value)
+ }
+ }
+}
diff --git a/trees/src/main/kotlin/bst/BalancingTree.kt b/trees/src/main/kotlin/bst/BalancingTree.kt
new file mode 100644
index 0000000..9e7a1c4
--- /dev/null
+++ b/trees/src/main/kotlin/bst/BalancingTree.kt
@@ -0,0 +1,32 @@
+package bst
+
+import bst.nodes.BinaryNode
+
+/**
+ * An abstract class representing a balancing tree data structure that extends the AbstractBST class.
+ *
+ * @param K the type of keys maintained by this balancing tree.
+ * @param V the type of mapped values.
+ * @param Self the type of the binary nodes in this balancing tree.
+ */
+
+abstract class BalancingTree, V, Self : BinaryNode> : AbstractBST() {
+
+ /**
+ * Rotates the given node to the left to rebalance the tree.
+ *
+ * @param node the node to rotate.
+ * @return the rotated node.
+ */
+
+ protected abstract fun rotateLeft(node: Self): Self
+
+ /**
+ * Rotates the given node to the right to rebalance the tree.
+ *
+ * @param node the node to rotate.
+ * @return the rotated node.
+ */
+
+ protected abstract fun rotateRight(node: Self): Self
+}
diff --git a/trees/src/main/kotlin/bst/RedBlackTree.kt b/trees/src/main/kotlin/bst/RedBlackTree.kt
new file mode 100644
index 0000000..02a2c5a
--- /dev/null
+++ b/trees/src/main/kotlin/bst/RedBlackTree.kt
@@ -0,0 +1,325 @@
+package bst
+
+import bst.nodes.RBTNode
+
+/**
+ * RedBlackTree represents a red-black tree data structure and extends the BalancingTree class.
+ *
+ * @param The type of the keys in the tree, which must be comparable.
+ * @param The type of the values in the tree.
+ * @property key The key of the root node of the tree.
+ * @property value The value of the root node of the tree.
+ * @constructor Creates a new instance of the RedBlackTree class with the given key and value.
+ */
+class RedBlackTree, V>(@Transient val key: K? = null, @Transient val value: V? = null) : BalancingTree>() {
+
+ /**
+ * Initializes a new Red-Black Tree node with the given key and value.
+ *
+ * @param key The key of the new node.
+ * @param value The value of the new node.
+ * @return The new node.
+ */
+ override fun initNode(key: K, value: V): RBTNode = RBTNode(key, value)
+
+ /**
+ * Initializes the root node of the tree with the given key and value if they are not null.
+ */
+ init {
+ if (key != null && value != null) {
+ rootNode = initNode(key, value)
+ }
+ }
+
+ /**
+ * Checks if the given Red-Black Tree node is red.
+ *
+ * @param node The node to check.
+ * @return true if the node is not null and has the color red, false otherwise.
+ */
+ private fun isRed(node: RBTNode?): Boolean {
+ return node != null && node.color == RBTNode.Color.RED
+ }
+
+ /**
+ * Inserts a new node with the given key and value into the Red-Black Tree.
+ *
+ * @param key The key of the new node.
+ * @param value The value of the new node.
+ */
+ override fun insert(key: K, value: V) {
+ insertNode(key, value)
+ }
+
+ /**
+ * Inserts a new node with the given key and value into the Red-Black Tree.
+ *
+ * @param key The key of the new node.
+ * @param value The value of the new node.
+ */
+ private fun insertNode(key: K, value: V) {
+ if (rootNode == null) {
+ /* Empty tree case */
+ rootNode = initNode(key, value)
+ rootNode?.color = RBTNode.Color.BLACK
+ return
+ } else {
+ val head = initNode(key, value) // False tree root
+
+ var grandparent: RBTNode? = null
+ var helper: RBTNode = head
+ var parent: RBTNode? = null
+
+ helper.right = rootNode
+ var iter: RBTNode? = helper.right
+ /*
+ true is for right child
+ false is for left child
+ */
+ var direction = false
+ /* Last direction */
+ var last = false
+
+ // Search down the tree
+ while (true) {
+ if (iter == null) {
+ // Insert new node at the bottom
+ iter = initNode(key, value)
+ if (direction) parent?.right = iter else parent?.left = iter
+ } else if (isRed(iter.left) && isRed(iter.right)) {
+ // Color flip
+ iter.color = RBTNode.Color.RED
+ iter.left?.color = RBTNode.Color.BLACK
+ iter.right?.color = RBTNode.Color.BLACK
+ }
+ // Fix red violation
+ if (isRed(iter) && isRed(parent) && grandparent != null) {
+ val dir2 = helper.child(true) == grandparent
+ if (dir2) {
+ if (iter == parent?.child(last)) {
+ helper.right = rotate(grandparent, !last)
+ } else {
+ helper.right = doubleRotate(grandparent, !last)
+ }
+ } else {
+ if (iter == parent?.child(last)) {
+ helper.left = rotate(grandparent, !last)
+ } else {
+ helper.left = doubleRotate(grandparent, !last)
+ }
+ }
+ }
+
+ // Stop if found
+ if (iter.key == key) {
+ iter.value = value
+ break
+ }
+
+ last = direction
+ direction = iter.key < key
+
+ // Update helpers
+ helper = grandparent ?: helper
+ grandparent = parent
+ parent = iter
+ iter = iter.child(direction)
+ }
+
+ // Update root
+ rootNode = head.right
+ }
+ rootNode?.color = RBTNode.Color.BLACK
+ }
+
+ /**
+ * Removes the node with the given key from the binary search tree.
+ * This function calls the removeNode function with the given key as its parameter.
+ * @param key the key of the node to be removed
+ */
+ override fun remove(key: K) {
+ removeNode(key)
+ }
+
+ /**
+ * Update the root of the Red-Black tree to the head child node and make the root black for simplified logic.
+ * @return 1 after the root is updated and colored black
+ * Removes the node with the given key from the binary search tree.
+ * @param key the key of the node to be removed
+ * @throws IllegalStateException if the root node of the tree is null
+ */
+
+ private fun removeNode(key: K): Int {
+ // Code implementation for removing node from the binary search tree
+ if (rootNode != null) {
+ /*
+ False tree root.
+ */
+ val head = initNode(
+ key,
+ rootNode?.value
+ ?: throw IllegalStateException("Root of the tree cannot be null")
+ )
+ var iter: RBTNode = head
+ var parent: RBTNode? = null
+ var grandparent: RBTNode?
+ var nodeToDelete: RBTNode? = null
+ /*
+ true is for right child
+ false is for left child
+ */
+ var direction = true
+
+ iter.right = rootNode
+
+ /*
+ Search and push a red node down
+ to fix red violations as we go
+ */
+ while (iter.child(direction) != null) {
+ val last = direction
+
+ /* Move the helpers down */
+ grandparent = parent
+ parent = iter
+ iter = parent.child(direction) ?: throw IllegalStateException("Parent node cannot be null")
+ direction = iter.key < key
+
+ /*
+ Save the node with matching data and keep
+ going; we'll do removal tasks at the end
+ */
+ if (iter.key == key) {
+ nodeToDelete = iter
+ }
+ /* Push the red node down with rotations and color flips */
+ if (!isRed(iter) && !isRed(iter.child(direction))) {
+ if (isRed(iter.child(!direction))) {
+ if (last) {
+ parent.right = rotate(iter, direction)
+ } else {
+ parent.left = rotate(iter, direction)
+ }
+ parent = parent.child(last)
+ } else if (!isRed(iter.child(!direction))) {
+ val sibling = parent.child(!last)
+
+ if (sibling != null) {
+ if (!isRed(sibling.child(!last)) && !isRed(sibling.child(last))) {
+ /* Color flip */
+ parent.color = RBTNode.Color.BLACK
+ sibling.color = RBTNode.Color.RED
+ iter.color = RBTNode.Color.RED
+ } else {
+ val direction2 = (
+ grandparent?.right
+ ?: throw IllegalStateException("Grandparent node cannot be null")
+ ) == parent
+
+ if (isRed(sibling.child(last))) {
+ if (direction2) {
+ grandparent.right = doubleRotate(parent, last)
+ } else {
+ grandparent.left = doubleRotate(parent, last)
+ }
+ } else if (isRed(sibling.child(!last))) {
+ if (direction2) {
+ grandparent.right = rotate(parent, last)
+ } else {
+ grandparent.left = rotate(parent, last)
+ }
+ }
+ /* Ensure correct coloring */
+ iter.color = RBTNode.Color.RED
+ grandparent.child(direction2)?.color = RBTNode.Color.RED
+ grandparent.child(direction2)?.left?.color = RBTNode.Color.BLACK
+ grandparent.child(direction2)?.right?.color = RBTNode.Color.BLACK
+ }
+ }
+ }
+ }
+ }
+
+ /* Replace and remove the saved node */
+ if (nodeToDelete != null) {
+ nodeToDelete.key = iter.key
+ nodeToDelete.value = iter.value
+ if (parent?.right == iter) {
+ parent.right = iter.child(iter.left == null)
+ } else {
+ parent?.left = iter.child(iter.left == null)
+ }
+ }
+
+ /* Update the root (it may be different) */
+ rootNode = head.child(true)
+
+ /* Make the root black for simplified logic */
+ rootNode?.color = RBTNode.Color.BLACK
+ }
+ return 1
+ }
+
+ /**
+ * Performs a single rotation on the given node in the specified direction.
+ * @param node the node to be rotated
+ * @param dir the direction of the rotation (true for right, false for left)
+ * @return the child node after the rotation
+ */
+
+ private fun rotate(node: RBTNode, dir: Boolean): RBTNode {
+ // Code implementation for performing a single rotation on the given node
+ val childNode: RBTNode = if (dir) {
+ rotateRight(node)
+ } else {
+ rotateLeft(node)
+ }
+ node.color = RBTNode.Color.RED
+ childNode.color = RBTNode.Color.BLACK
+ return childNode
+ }
+
+ /**
+ * Performs a double rotation on the given node in the specified direction.
+ * @param node the node to be double rotated
+ * @param dir the direction of the double rotation (true for right, false for left)
+ * @return the child node after the double rotation
+ */
+
+ private fun doubleRotate(node: RBTNode, dir: Boolean): RBTNode {
+ if (dir) {
+ node.left = node.left?.let { rotate(it, false) }
+ } else {
+ node.right = node.right?.let { rotate(it, true) }
+ }
+ return rotate(node, dir)
+ }
+
+ /**
+ * Rotates the given node to the left to rebalance the tree.
+ * @param node the node to be rotated to the left
+ * @return the new node after the rotation
+ * @throws IllegalStateException if the node's right child is null
+ */
+
+ override fun rotateLeft(node: RBTNode): RBTNode {
+ val right = node.right ?: throw IllegalStateException("Node's right child cannot be null")
+ node.right = right.left
+ right.left = node
+ return right
+ }
+
+ /**
+ * Rotates the given node to the right to rebalance the tree.
+ * @param node the node to be rotated to the right
+ * @return the new node after the rotation
+ * @throws IllegalStateException if the node's left child is null
+ */
+
+ override fun rotateRight(node: RBTNode): RBTNode {
+ val left = node.left ?: throw IllegalStateException("Node's left child cannot be null")
+ node.left = left.right
+ left.right = node
+ return left
+ }
+}
diff --git a/trees/src/main/kotlin/bst/Tree.kt b/trees/src/main/kotlin/bst/Tree.kt
new file mode 100644
index 0000000..af98e87
--- /dev/null
+++ b/trees/src/main/kotlin/bst/Tree.kt
@@ -0,0 +1,33 @@
+package bst
+
+/**
+ * An interface for a binary search tree.
+ * @param K the type of keys stored in the tree, must implement Comparable
+ * @param V the type of values stored in the tree
+ */
+
+interface Tree, V> {
+
+ /**
+ * Inserts a key-value pair into the tree.
+ * @param key the key to insert
+ * @param value the value to associate with the key
+ */
+
+ fun insert(key: K, value: V)
+
+ /**
+ * Removes the key-value pair with the given key from the tree.
+ * @param key the key of the pair to remove
+ */
+
+ fun remove(key: K)
+
+ /**
+ * Finds the value associated with the given key in the tree.
+ * @param key the key to search for in the tree
+ * @return the value associated with the given key if it exists, otherwise null
+ */
+
+ fun find(key: K): V?
+}
diff --git a/trees/src/main/kotlin/bst/db/controllers/Controller.kt b/trees/src/main/kotlin/bst/db/controllers/Controller.kt
new file mode 100644
index 0000000..e2b19e2
--- /dev/null
+++ b/trees/src/main/kotlin/bst/db/controllers/Controller.kt
@@ -0,0 +1,35 @@
+package bst.db.controllers
+
+import bst.AbstractBST
+import bst.nodes.BinaryNode
+
+/**
+ * The Controller interface defines the operations for managing binary search trees (BSTs) in the database.
+ *
+ * @param N the type of BinaryNode used in the BST
+ * @param T the type of AbstractBST implementation
+ */
+interface Controller, T : AbstractBST> {
+ /**
+ * Saves a BST with the specified name to the database.
+ *
+ * @param tree the BST to save
+ * @param treeName the name of the BST
+ */
+ fun saveTree(tree: T, treeName: String)
+
+ /**
+ * Retrieves a BST with the specified name from the database.
+ *
+ * @param treeName the name of the BST to retrieve
+ * @return the retrieved BST object, or null if the BST is not found
+ */
+ fun getTree(treeName: String): T?
+
+ /**
+ * Removes a BST with the specified name from the database.
+ *
+ * @param treeName the name of the BST to remove
+ */
+ fun removeTree(treeName: String)
+}
diff --git a/trees/src/main/kotlin/bst/db/controllers/JsonController.kt b/trees/src/main/kotlin/bst/db/controllers/JsonController.kt
new file mode 100644
index 0000000..c95d0d1
--- /dev/null
+++ b/trees/src/main/kotlin/bst/db/controllers/JsonController.kt
@@ -0,0 +1,77 @@
+package bst.db.controllers
+
+import bst.AVLTree
+import bst.nodes.AVLNode
+import com.google.gson.Gson
+import java.io.File
+import java.io.FileReader
+import java.io.FileWriter
+
+/**
+ * The JsonController class implements the Controller interface for managing AVL trees stored in JSON files.
+ */
+class JsonController : Controller, AVLTree> {
+ /**
+ * The path to the folder where JSON files are stored.
+ */
+ val folderPath = "json"
+
+ /**
+ * Saves an AVL tree with the specified name to a JSON file.
+ *
+ * @param tree the AVL tree to save
+ * @param treeName the name of the tree
+ */
+ override fun saveTree(tree: AVLTree, treeName: String) {
+ val gson = Gson()
+ try {
+ val writer = FileWriter("${this.folderPath}/$treeName.json")
+ gson.toJson(tree, writer)
+ writer.close()
+ } catch (e: Exception) {
+ println("Write error")
+ }
+ }
+
+ /**
+ * Retrieves an AVL tree with the specified name from a JSON file.
+ *
+ * @param treeName the name of the tree to retrieve
+ * @return the retrieved AVL tree object, or null if the tree is not found or an error occurs
+ */
+ override fun getTree(treeName: String): AVLTree? {
+ val gson = Gson()
+ return try {
+ val reader = FileReader("${this.folderPath}/$treeName.json")
+ val tree = gson.fromJson(reader, AVLTree()::class.java)
+ reader.close()
+ tree
+ } catch (e: Exception) {
+ println("Read error")
+ null
+ }
+ }
+
+ /**
+ * Removes an AVL tree with the specified name by deleting the corresponding JSON file.
+ *
+ * @param treeName the name of the tree to remove
+ */
+ override fun removeTree(treeName: String) {
+ File("${this.folderPath}/$treeName.json").delete()
+ }
+
+ /**
+ * Retrieves a list of names of all available AVL trees stored as JSON files.
+ *
+ * @return a list of tree names
+ */
+ fun getAllTrees(): List {
+ val jsonFiles = File(folderPath).listFiles { file -> file.extension == "json" }
+ val jsonNames = mutableListOf()
+ jsonFiles?.forEach { file ->
+ jsonNames.add(file.name.removeSuffix(".json"))
+ }
+ return jsonNames
+ }
+}
diff --git a/trees/src/main/kotlin/bst/db/controllers/Neo4jController.kt b/trees/src/main/kotlin/bst/db/controllers/Neo4jController.kt
new file mode 100644
index 0000000..003e2af
--- /dev/null
+++ b/trees/src/main/kotlin/bst/db/controllers/Neo4jController.kt
@@ -0,0 +1,212 @@
+package bst.db.controllers
+
+import bst.RedBlackTree
+import bst.db.models.neo4j.TreeEntity
+import bst.db.models.neo4j.TreeNodeEntity
+import bst.db.serializeClasses.SerializableNode
+import bst.db.serializeClasses.SerializableTree
+import bst.nodes.RBTNode
+import bst.nodes.RBTNode.Color
+import org.neo4j.ogm.config.Configuration
+import org.neo4j.ogm.session.SessionFactory
+
+/**
+ * Controller class for managing Red-Black Trees stored in a Neo4j database.
+ */
+class Neo4jController : Controller, RedBlackTree> {
+ /**
+ * The Neo4j database configuration.
+ */
+ private val config = Configuration.Builder()
+ .uri("bolt://localhost")
+ .credentials("neo4j", "password")
+ .build()
+
+ /**
+ * The session factory for creating database sessions.
+ */
+ private val sessionFactory = SessionFactory(config, "bst")
+
+ /**
+ * The database session.
+ */
+ private val session = sessionFactory.openSession()
+
+ /**
+ * Converts an RBTNode object to a SerializableNode object.
+ *
+ * @return the SerializableNode representation of the RBTNode
+ */
+ private fun RBTNode<*, *>?.toSerializableNode(): SerializableNode? {
+ if (this == null) {
+ return null
+ }
+ return SerializableNode(
+ key.toString(),
+ value.toString(),
+ 0.0,
+ 0.0,
+ color.toString(),
+ left?.toSerializableNode(),
+ right?.toSerializableNode()
+ )
+ }
+
+ /**
+ * Converts a RedBlackTree object to a SerializableTree object.
+ *
+ * @param treeName the name of the tree
+ * @return the SerializableTree representation of the RedBlackTree
+ */
+ private fun RedBlackTree<*, *>.toSerializableTree(treeName: String): SerializableTree {
+ return SerializableTree(treeName, rootNode?.toSerializableNode())
+ }
+
+ /**
+ * Converts a TreeNodeEntity object to a SerializableNode object.
+ *
+ * @return the SerializableNode representation of the TreeNodeEntity
+ */
+ private fun TreeNodeEntity.toSerializableNode(): SerializableNode {
+ return SerializableNode(key, value, x, y, metadata, left?.toSerializableNode(), right?.toSerializableNode())
+ }
+
+ /**
+ * Converts a TreeEntity object to a SerializableTree object.
+ *
+ * @return the SerializableTree representation of the TreeEntity
+ */
+ private fun TreeEntity.toSerializableTree(): SerializableTree {
+ return SerializableTree(treeName, rootNode?.toSerializableNode())
+ }
+
+ /**
+ * Converts a SerializableNode object to a TreeNodeEntity object.
+ *
+ * @return the TreeNodeEntity representation of the SerializableNode
+ */
+ private fun SerializableNode.toNodeEntity(): TreeNodeEntity {
+ return TreeNodeEntity(key, value, x, y, metadata, leftNode?.toNodeEntity(), rightNode?.toNodeEntity())
+ }
+
+ /**
+ * Converts a SerializableTree object to a TreeEntity object.
+ *
+ * @return the TreeEntity representation of the SerializableTree
+ */
+ private fun SerializableTree.toTreeEntity(): TreeEntity {
+ return TreeEntity(treeName, rootNode?.toNodeEntity())
+ }
+
+ /**
+ * Deserializes a SerializableNode object to an RBTNode object.
+ *
+ * @return the deserialized RBTNode object
+ */
+ private fun deserializeNode(node: SerializableNode?): RBTNode? {
+ node ?: return null
+ val rbtNode = RBTNode(
+ key = node.key.toInt(),
+ value = node.value,
+ color = deserializeMetadata(node.metadata)
+ )
+ rbtNode.left = deserializeNode(node.leftNode)
+ rbtNode.right = deserializeNode(node.rightNode)
+ return rbtNode
+ }
+
+ /**
+ * Deserializes a SerializableTree object to a RedBlackTree object.
+ *
+ * @return the deserialized RedBlackTree object
+ */
+ private fun deserializeTree(tree: SerializableTree): RedBlackTree {
+ val rbTree = RedBlackTree()
+ rbTree.rootNode = deserializeNode(tree.rootNode)
+ return rbTree
+ }
+
+ /**
+ * Deserializes a metadata string to a Color enum.
+ *
+ * @return the deserialized Color enum
+ * @throws NoSuchFieldException if the metadata does not match any Color values
+ */
+ private fun deserializeMetadata(metadata: String?): Color {
+ return when (metadata) {
+ "RED" -> Color.RED
+ "BLACK" -> Color.BLACK
+ else -> throw NoSuchFieldException("Node's color must be either RED or BLACK")
+ }
+ }
+
+ /**
+ * Saves a RedBlackTree to the Neo4j database with the specified name.
+ *
+ * @param tree the RedBlackTree to save
+ * @param treeName the name of the tree
+ */
+ override fun saveTree(tree: RedBlackTree, treeName: String) {
+ removeTree(treeName)
+ val entityTree = tree.toSerializableTree(treeName).toTreeEntity()
+ entityTree.treeName = treeName
+ session.save(entityTree)
+ session.query(
+ "MATCH (n: BinaryNode) WHERE NOT (n)--() DELETE (n)",
+ mapOf()
+ )
+ }
+
+ /**
+ * Removes a RedBlackTree with the specified name from the Neo4j database.
+ *
+ * @param treeName the name of the tree to remove
+ */
+ override fun removeTree(treeName: String) {
+ session.query(
+ "MATCH (n)-[r *0..]->(m) " + "WHERE n.treeName = \$treeName DETACH DELETE m",
+ mapOf("treeName" to treeName)
+ )
+ }
+
+ /**
+ * Retrieves a RedBlackTree with the specified name from the Neo4j database.
+ *
+ * @param treeName the name of the tree to retrieve
+ * @return the retrieved RedBlackTree object, or null if the tree is not found
+ */
+ override fun getTree(treeName: String): RedBlackTree? {
+ val tree = loadTree(treeName)
+ return tree?.let { deserializeTree(it.toSerializableTree()) }
+ }
+
+ /**
+ * Loads a TreeEntity from the Neo4j database with the specified name.
+ *
+ * @param treeName the name of the tree to load
+ * @return the loaded TreeEntity object, or null if the tree is not found
+ */
+ private fun loadTree(treeName: String): TreeEntity? {
+ return session.queryForObject(
+ TreeEntity::class.java,
+ "MATCH (n)-[r *1..]-(m) " + "WHERE n.treeName = \$treeName RETURN n, r, m",
+ mapOf("treeName" to treeName)
+ ) ?: null
+ }
+
+ /**
+ * Closes the Neo4j session and session factory.
+ */
+ fun close() {
+ session.clear()
+ sessionFactory.close()
+ }
+
+ /**
+ * Retrieves the names of all the trees stored in the Neo4j database.
+ *
+ * @return a list of tree names
+ */
+ fun getNames() = session.query("MATCH (n: TreeEntity) RETURN n.treeName", mapOf())
+ .flatMap { it.values.map { value -> value.toString() } }
+}
diff --git a/trees/src/main/kotlin/bst/db/controllers/SQLController.kt b/trees/src/main/kotlin/bst/db/controllers/SQLController.kt
new file mode 100644
index 0000000..49f7724
--- /dev/null
+++ b/trees/src/main/kotlin/bst/db/controllers/SQLController.kt
@@ -0,0 +1,255 @@
+package bst.db.controllers
+
+import bst.BSTree
+import bst.db.models.sql.Node
+import bst.db.models.sql.Nodes
+import bst.db.models.sql.Tree
+import bst.db.models.sql.Trees
+import bst.db.serializeClasses.SerializableNode
+import bst.db.serializeClasses.SerializableTree
+import bst.nodes.BSTNode
+import org.jetbrains.exposed.exceptions.ExposedSQLException
+import org.jetbrains.exposed.sql.Database
+import org.jetbrains.exposed.sql.SchemaUtils
+import org.jetbrains.exposed.sql.StdOutSqlLogger
+import org.jetbrains.exposed.sql.addLogger
+import org.jetbrains.exposed.sql.selectAll
+import org.jetbrains.exposed.sql.transactions.transaction
+
+/**
+ * A controller class for interacting with a binary search tree (BST) stored in an SQL database.
+ * It provides methods for saving, retrieving, and removing BSTs from the database.
+ */
+class SQLController : Controller, BSTree> {
+ /**
+ * Connects to the SQL database and creates the required tables if they don't exist.
+ */
+ private fun connectDB() {
+ Database.connect(
+ "jdbc:postgresql://localhost:5432/test",
+ driver = "org.postgresql.Driver",
+ user = "test",
+ password = "test-test"
+ )
+ createTables()
+ }
+
+ /**
+ * Removes a tree from the database with the specified name.
+ *
+ * @param treeName the name of the tree to remove
+ */
+ override fun removeTree(treeName: String) {
+ transaction {
+ try {
+ Tree.find { (Trees.name eq treeName) }
+ .firstOrNull()?.delete()
+ } catch (e: ExposedSQLException) {
+ println("Tree does not exists")
+ }
+ }
+ }
+
+ /**
+ * Serializes a BSTNode object into a SerializableNode object.
+ *
+ * @param node the BSTNode to serialize
+ * @return the serialized SerializableNode object
+ */
+ private fun serializeNode(node: BSTNode?): SerializableNode? {
+ return if (node == null) {
+ null
+ } else {
+ val serializableNode = SerializableNode(
+ key = node.key.toString(),
+ value = node.value,
+ leftNode = null,
+ rightNode = null
+ )
+ serializableNode.rightNode = serializeNode(node.right)
+ serializableNode.leftNode = serializeNode(node.left)
+ serializableNode
+ }
+ }
+
+ /**
+ * Serializes a BSTree object into a SerializableTree object.
+ *
+ * @param tree the BSTree to serialize
+ * @param treeName the name of the tree
+ * @return the serialized SerializableTree object
+ */
+ private fun serializeTree(tree: BSTree, treeName: String): SerializableTree? {
+ return tree.rootNode?.let { serializeNode(it) }
+ ?.let { SerializableTree(treeName = treeName, rootNode = it) }
+ }
+
+ /**
+ * Creates the required tables in the database if they don't exist.
+ */
+ private fun createTables() {
+ transaction {
+ SchemaUtils.create(Trees)
+ SchemaUtils.create(Nodes)
+ }
+ }
+
+ /**
+ * Converts a SerializableNode object into a Node object and associates it with the specified Tree object.
+ *
+ * @param treeDao the Tree object to associate the Node with
+ * @return the created Node object
+ */
+ private fun SerializableNode.toNodeDao(treeDao: Tree): Node {
+ return Node.new {
+ key = this@toNodeDao.key
+ value = this@toNodeDao.value
+ x = this@toNodeDao.x
+ y = this@toNodeDao.y
+ left = this@toNodeDao.leftNode?.toNodeDao(treeDao)
+ right = this@toNodeDao.rightNode?.toNodeDao(treeDao)
+ tree = treeDao
+ }
+ }
+
+ /**
+ * Saves a BSTree object to the database with the specified name.
+ *
+ * @param tree the BSTree to save
+ * @param treeName the name of the tree
+ */
+ override fun saveTree(tree: BSTree, treeName: String) {
+ connectDB()
+ removeTree(treeName)
+ val serializedTree = serializeTree(tree, treeName)
+ transaction {
+ addLogger(StdOutSqlLogger)
+ createTables()
+ val daoTree = Tree.new {
+ if (serializedTree != null) name = serializedTree.treeName
+ }
+ daoTree.rootNode = serializedTree?.rootNode?.toNodeDao(daoTree)
+ }
+ }
+
+ /**
+ * Converts a Node object into a SerializableNode object.
+ *
+ * @param treeDao the associated Tree object
+ * @return the serialized SerializableNode object
+ */
+ private fun Node.getSerializedNode(treeDao: Tree): SerializableNode {
+ return SerializableNode(
+ this@getSerializedNode.key,
+ this@getSerializedNode.value,
+ this@getSerializedNode.x,
+ this@getSerializedNode.y,
+ null,
+ this@getSerializedNode.left?.getSerializedNode(treeDao),
+ this@getSerializedNode.right?.getSerializedNode(treeDao)
+ )
+ }
+
+ /**
+ * Finds a SerializableTree object with the specified name in the database.
+ *
+ * @param treeName the name of the tree to find
+ * @return the found SerializableTree object, or null if not found
+ */
+ private fun findTree(treeName: String): SerializableTree? {
+ connectDB()
+ val treeDAO = Tree.find { Trees.name eq treeName }.firstOrNull() ?: return null
+ return treeDAO.rootNode?.getSerializedNode(treeDAO)?.let {
+ SerializableTree(
+ treeName,
+ it
+ )
+ }
+ }
+
+ /**
+ * Checks if a given string is numeric.
+ *
+ * @param s the string to check
+ * @return true if the string is numeric, false otherwise
+ */
+ private fun isNumeric(s: String): Boolean {
+ return try {
+ s.toInt()
+ true
+ } catch (e: NumberFormatException) {
+ false
+ }
+ }
+
+ /**
+ * Deserializes a SerializableNode object with integer keys into a BSTNode object.
+ *
+ * @param node the SerializableNode to deserialize
+ * @return the deserialized BSTNode object
+ */
+ private fun deserializeNodeDoubleKey(node: SerializableNode?): BSTNode? {
+ return if (node == null) {
+ null
+ } else {
+ val deserializableNode = BSTNode(key = node.key.toInt(), value = node.value)
+ deserializableNode.right = deserializeNodeDoubleKey(node.rightNode)
+ deserializableNode.left = deserializeNodeDoubleKey(node.leftNode)
+ deserializableNode
+ }
+ }
+
+ /**
+ * Deserializes a SerializableTree object into a BSTree object.
+ * The deserialization process converts the SerializableTree's root node
+ * and its children SerializableNodes into BSTNodes.
+ *
+ * @param tree the SerializableTree to deserialize
+ * @return the deserialized BSTree object, or null if the serialization is invalid
+ */
+ private fun deserializeTree(tree: SerializableTree?): BSTree? {
+ if (tree != null) {
+ if (isNumeric(tree.rootNode!!.key)) {
+ val rootNode = deserializeNodeDoubleKey(tree.rootNode)
+ val deserializedTree: BSTree = BSTree(rootNode?.key, rootNode?.value)
+ deserializedTree.rootNode = rootNode
+ return deserializedTree
+ }
+ }
+ return null
+ }
+
+ /**
+ * Retrieves a BSTree object from the database with the specified name.
+ * The retrieval process involves finding the SerializableTree with the given name,
+ * deserializing it, and converting it into a BSTree.
+ *
+ * @param treeName the name of the tree to retrieve
+ * @return the retrieved BSTree object, or null if the tree is not found in the database
+ */
+ override fun getTree(treeName: String): BSTree? {
+ var deserializedTree: SerializableTree? = null
+ transaction {
+ deserializedTree = findTree(treeName)
+ }
+ return deserializeTree(deserializedTree)
+ }
+
+ /**
+ * Retrieves the names of all the trees stored in the database.
+ *
+ * @return a list of tree names
+ */
+ fun getAllTrees(): List {
+ val notes = mutableListOf()
+ connectDB()
+ transaction {
+ Trees.selectAll().forEach {
+ val name = it[Trees.name]
+ notes.add(name)
+ }
+ }
+
+ return notes
+ }
+}
diff --git a/trees/src/main/kotlin/bst/db/models/neo4j/TreeEntity.kt b/trees/src/main/kotlin/bst/db/models/neo4j/TreeEntity.kt
new file mode 100644
index 0000000..abb9e6d
--- /dev/null
+++ b/trees/src/main/kotlin/bst/db/models/neo4j/TreeEntity.kt
@@ -0,0 +1,22 @@
+package bst.db.models.neo4j
+
+import org.neo4j.ogm.annotation.GeneratedValue
+import org.neo4j.ogm.annotation.Id
+import org.neo4j.ogm.annotation.NodeEntity
+
+/**
+ * Represents a tree entity in the Neo4j database.
+ *
+ * @property treeName The name of the tree.
+ * @property rootNode The root node of the tree.
+ * @property id The unique identifier of the tree entity.
+ */
+@NodeEntity
+class TreeEntity(
+ var treeName: String = "",
+ var rootNode: TreeNodeEntity? = null
+) {
+ @Id
+ @GeneratedValue
+ var id: Long? = null
+}
diff --git a/trees/src/main/kotlin/bst/db/models/neo4j/TreeNodeEntity.kt b/trees/src/main/kotlin/bst/db/models/neo4j/TreeNodeEntity.kt
new file mode 100644
index 0000000..0c387a9
--- /dev/null
+++ b/trees/src/main/kotlin/bst/db/models/neo4j/TreeNodeEntity.kt
@@ -0,0 +1,36 @@
+package bst.db.models.neo4j
+
+import org.neo4j.ogm.annotation.GeneratedValue
+import org.neo4j.ogm.annotation.Id
+import org.neo4j.ogm.annotation.NodeEntity
+import org.neo4j.ogm.annotation.Relationship
+
+/**
+ * Represents a node entity in a binary search tree stored in the Neo4j database.
+ *
+ * @property key The key of the node.
+ * @property value The value associated with the node.
+ * @property x The x-coordinate of the node in a visualization (default is 0.0).
+ * @property y The y-coordinate of the node in a visualization (default is 0.0).
+ * @property metadata Additional metadata associated with the node.
+ * @property left The left child node of the current node.
+ * @property right The right child node of the current node.
+ * @property id The unique identifier of the node entity.
+ */
+@NodeEntity
+class TreeNodeEntity(
+ val key: String,
+ val value: String,
+ val x: Double = 0.0,
+ val y: Double = 0.0,
+ var metadata: String? = null,
+ @Relationship(type = "LEFT") var left: TreeNodeEntity? = null,
+ @Relationship(type = "RIGHT") var right: TreeNodeEntity? = null
+) {
+ /**
+ * The unique identifier of the node entity.
+ */
+ @Id
+ @GeneratedValue
+ var id: Long? = null
+}
diff --git a/trees/src/main/kotlin/bst/db/models/sql/Node.kt b/trees/src/main/kotlin/bst/db/models/sql/Node.kt
new file mode 100644
index 0000000..5ce7c42
--- /dev/null
+++ b/trees/src/main/kotlin/bst/db/models/sql/Node.kt
@@ -0,0 +1,34 @@
+package bst.db.models.sql
+
+import org.jetbrains.exposed.dao.IntEntity
+import org.jetbrains.exposed.dao.IntEntityClass
+import org.jetbrains.exposed.dao.id.EntityID
+
+/**
+ * Represents a node entity in a binary search tree stored in the SQL database.
+ *
+ * @property id The unique identifier of the node entity.
+ * @property key The key of the node.
+ * @property value The value associated with the node.
+ * @property x The x-coordinate of the node in a visualization.
+ * @property y The y-coordinate of the node in a visualization.
+ * @property left The left child node of the current node.
+ * @property right The right child node of the current node.
+ * @property tree The tree to which the node belongs.
+ */
+class Node(id: EntityID) : IntEntity(id) {
+ companion object : IntEntityClass(Nodes)
+
+ var key by Nodes.key
+ var value by Nodes.value
+ var x by Nodes.x
+ var y by Nodes.y
+ var left by Node optionalReferencedOn Nodes.left
+ var right by Node optionalReferencedOn Nodes.right
+ var tree by Tree referencedOn Nodes.tree
+
+ /**
+ * Returns a string representation of the node.
+ */
+ override fun toString(): String = "Node(key = $key, value=$value, x=$x, y=$y, left=$left, right=$right, tree=$tree)"
+}
diff --git a/trees/src/main/kotlin/bst/db/models/sql/Nodes.kt b/trees/src/main/kotlin/bst/db/models/sql/Nodes.kt
new file mode 100644
index 0000000..2faa278
--- /dev/null
+++ b/trees/src/main/kotlin/bst/db/models/sql/Nodes.kt
@@ -0,0 +1,25 @@
+package bst.db.models.sql
+
+import org.jetbrains.exposed.dao.id.IntIdTable
+import org.jetbrains.exposed.sql.ReferenceOption
+
+/**
+ * Represents the database table for storing node entities in a binary search tree.
+ *
+ * @property key Column for the key of the node.
+ * @property value Column for the value associated with the node.
+ * @property x Column for the x-coordinate of the node in a visualization, with a default value of 0.0.
+ * @property y Column for the y-coordinate of the node in a visualization, with a default value of 0.0.
+ * @property left Column for the left child node reference, allowing null values.
+ * @property right Column for the right child node reference, allowing null values.
+ * @property tree Column for the tree reference to which the node belongs, with CASCADE delete behavior.
+ */
+object Nodes : IntIdTable("nodes") {
+ val key = varchar("key", length = 256)
+ val value = varchar("value", length = 256)
+ val x = double("x_coordinate").default(0.0)
+ val y = double("y_coordinate").default(0.0)
+ val left = reference("left", Nodes).nullable()
+ val right = reference("right", Nodes).nullable()
+ val tree = reference("tree", Trees, onDelete = ReferenceOption.CASCADE)
+}
diff --git a/trees/src/main/kotlin/bst/db/models/sql/Tree.kt b/trees/src/main/kotlin/bst/db/models/sql/Tree.kt
new file mode 100644
index 0000000..6160f0a
--- /dev/null
+++ b/trees/src/main/kotlin/bst/db/models/sql/Tree.kt
@@ -0,0 +1,24 @@
+package bst.db.models.sql
+
+import org.jetbrains.exposed.dao.IntEntity
+import org.jetbrains.exposed.dao.IntEntityClass
+import org.jetbrains.exposed.dao.id.EntityID
+
+/**
+ * Represents a tree entity in the SQL database.
+ *
+ * @property id The unique identifier of the tree entity.
+ * @property name The name of the tree.
+ * @property rootNode The root node of the tree, allowing null values.
+ */
+class Tree(id: EntityID) : IntEntity(id) {
+ companion object : IntEntityClass(Trees)
+
+ var name by Trees.name
+ var rootNode by Node optionalReferencedOn Trees.rootNode
+
+ /**
+ * Returns a string representation of the tree.
+ */
+ override fun toString(): String = "Node(key = $name, rootNode=$rootNode)"
+}
diff --git a/trees/src/main/kotlin/bst/db/models/sql/Trees.kt b/trees/src/main/kotlin/bst/db/models/sql/Trees.kt
new file mode 100644
index 0000000..571e320
--- /dev/null
+++ b/trees/src/main/kotlin/bst/db/models/sql/Trees.kt
@@ -0,0 +1,14 @@
+package bst.db.models.sql
+
+import org.jetbrains.exposed.dao.id.IntIdTable
+
+/**
+ * Represents the database table for storing tree entities in the SQL database.
+ *
+ * @property name Column for the name of the tree.
+ * @property rootNode Column for the root node reference of the tree, allowing null values.
+ */
+object Trees : IntIdTable("trees") {
+ val name = varchar("name", length = 128).uniqueIndex()
+ val rootNode = reference("rootNode", Nodes.id).nullable()
+}
diff --git a/trees/src/main/kotlin/bst/db/serializeClasses/SerializableNode.kt b/trees/src/main/kotlin/bst/db/serializeClasses/SerializableNode.kt
new file mode 100644
index 0000000..dd7bfde
--- /dev/null
+++ b/trees/src/main/kotlin/bst/db/serializeClasses/SerializableNode.kt
@@ -0,0 +1,25 @@
+package bst.db.serializeClasses
+
+import kotlinx.serialization.Serializable
+
+/**
+ * Represents a serializable node in a binary search tree.
+ *
+ * @property key The key of the node.
+ * @property value The value associated with the node.
+ * @property x The x-coordinate of the node in a visualization, with a default value of 0.0.
+ * @property y The y-coordinate of the node in a visualization, with a default value of 0.0.
+ * @property metadata Additional metadata associated with the node, nullable.
+ * @property leftNode The left child node, nullable.
+ * @property rightNode The right child node, nullable.
+ */
+@Serializable
+class SerializableNode(
+ val key: String,
+ val value: String,
+ var x: Double = 0.0,
+ var y: Double = 0.0,
+ var metadata: String? = null,
+ var leftNode: SerializableNode? = null,
+ var rightNode: SerializableNode? = null
+)
diff --git a/trees/src/main/kotlin/bst/db/serializeClasses/SerializableTree.kt b/trees/src/main/kotlin/bst/db/serializeClasses/SerializableTree.kt
new file mode 100644
index 0000000..a4cbc33
--- /dev/null
+++ b/trees/src/main/kotlin/bst/db/serializeClasses/SerializableTree.kt
@@ -0,0 +1,15 @@
+package bst.db.serializeClasses
+
+import kotlinx.serialization.Serializable
+
+/**
+ * Represents a serializable tree in a binary search tree structure.
+ *
+ * @property treeName The name of the tree.
+ * @property rootNode The root node of the tree, nullable.
+ */
+@Serializable
+class SerializableTree(
+ var treeName: String,
+ var rootNode: SerializableNode?
+)
diff --git a/trees/src/main/kotlin/bst/nodes/AVLNode.kt b/trees/src/main/kotlin/bst/nodes/AVLNode.kt
new file mode 100644
index 0000000..be665d6
--- /dev/null
+++ b/trees/src/main/kotlin/bst/nodes/AVLNode.kt
@@ -0,0 +1,21 @@
+package bst.nodes
+
+/**
+ * Represents a node in an AVL Tree.
+ *
+ * @param K the type of the key.
+ * @param V the type of the value.
+ * @param key the key associated with this node.
+ * @param value the value associated with this node.
+ * @param BinaryNode the parent class representing a binary node.
+ */
+
+class AVLNode, V>(
+ key: K,
+ value: V
+) : BinaryNode>(key, value) {
+ /**
+ * Represents the height of the node.
+ */
+ var height: Int = 0
+}
diff --git a/trees/src/main/kotlin/bst/nodes/BSTNode.kt b/trees/src/main/kotlin/bst/nodes/BSTNode.kt
new file mode 100644
index 0000000..ca1876e
--- /dev/null
+++ b/trees/src/main/kotlin/bst/nodes/BSTNode.kt
@@ -0,0 +1,16 @@
+package bst.nodes
+
+/**
+ * Represents a node in a Binary Search Tree.
+ *
+ * @param K the type of the key.
+ * @param V the type of the value.
+ * @param key the key associated with this node.
+ * @param value the value associated with this node.
+ * @param BinaryNode the parent class representing a binary node.
+ */
+
+class BSTNode, V>(
+ key: K,
+ value: V
+) : BinaryNode>(key, value)
diff --git a/trees/src/main/kotlin/bst/nodes/BinaryNode.kt b/trees/src/main/kotlin/bst/nodes/BinaryNode.kt
new file mode 100644
index 0000000..60d2b95
--- /dev/null
+++ b/trees/src/main/kotlin/bst/nodes/BinaryNode.kt
@@ -0,0 +1,26 @@
+package bst.nodes
+
+/**
+ * Represents a binary node in a binary tree.
+ *
+ * @param K the type of the key.
+ * @param V the type of the value.
+ * @param Self the type of the node itself.
+ * @param key the key associated with this node.
+ * @param value the value associated with this node.
+ */
+
+abstract class BinaryNode, V, Self : BinaryNode>(
+ var key: K,
+ var value: V
+) {
+ /**
+ * Represents the left child node of this node.
+ */
+ var left: Self? = null
+
+ /**
+ * Represents the right child node of this node.
+ */
+ var right: Self? = null
+}
diff --git a/trees/src/main/kotlin/bst/nodes/RBTNode.kt b/trees/src/main/kotlin/bst/nodes/RBTNode.kt
new file mode 100644
index 0000000..77592a6
--- /dev/null
+++ b/trees/src/main/kotlin/bst/nodes/RBTNode.kt
@@ -0,0 +1,34 @@
+package bst.nodes
+
+/**
+ * Represents a node in a Red-Black Tree.
+ *
+ * @param K the type of the key.
+ * @param V the type of the value.
+ * @param key the key associated with this node.
+ * @param value the value associated with this node.
+ * @param color the color of the node.
+ * @param BinaryNode the parent class representing a binary node.
+ */
+
+class RBTNode, V>(
+ key: K,
+ value: V,
+ var color: Color = Color.RED
+) : BinaryNode>(key, value) {
+
+ /**
+ * Returns the child node of this node based on the given flag.
+ *
+ * @param f a flag indicating whether to return the right child (true) or the left child (false).
+ * @return the child node of this node based on the given flag.
+ */
+ internal fun child(f: Boolean) = if (f) right else left
+
+ /**
+ * Represents the color of the node.
+ */
+ enum class Color {
+ RED, BLACK
+ }
+}
diff --git a/trees/src/main/resources/simplelogger.properties b/trees/src/main/resources/simplelogger.properties
new file mode 100644
index 0000000..8c3588c
--- /dev/null
+++ b/trees/src/main/resources/simplelogger.properties
@@ -0,0 +1,3 @@
+org.slf4j.simpleLogger.defaultLogLevel=info
+org.slf4j.simpleLogger.logFile=System.out
+org.slf4j.simpleLogger.log.org.neo4j.ogm.drivers.bolt.request.BoltRequest=debug
diff --git a/trees/src/test/kotlin/bst/AvlTest.kt b/trees/src/test/kotlin/bst/AvlTest.kt
new file mode 100644
index 0000000..fba8807
--- /dev/null
+++ b/trees/src/test/kotlin/bst/AvlTest.kt
@@ -0,0 +1,175 @@
+package bst
+
+import bst.nodes.AVLNode
+import org.junit.jupiter.api.Assertions.assertEquals
+import org.junit.jupiter.api.Assertions.assertNull
+import org.junit.jupiter.api.Assertions.assertTrue
+import org.junit.jupiter.api.BeforeEach
+import org.junit.jupiter.api.Nested
+import org.junit.jupiter.api.Test
+import kotlin.math.max
+
+class AvlTest {
+ private fun , V> isAvl(node: AVLNode?): Boolean {
+ if (node == null) return true
+ return isAvl(node.left) &&
+ isAvl(node.right) &&
+ (subtreeHeight(node.left) - subtreeHeight(node.right) in -1..1)
+ }
+
+ private fun , V> subtreeHeight(node: AVLNode?): Int {
+ if (node == null) return 0
+ return max(subtreeHeight(node.left), subtreeHeight(node.right)) + 1
+ }
+
+ private fun , V> countNodes(node: AVLNode?): Int {
+ if (node == null) return 0
+ return countNodes(node.left) + countNodes(node.right) + 1
+ }
+
+ private lateinit var tree: AVLTree
+ private val values = IntArray(1000) { it + 1 }
+
+ @BeforeEach
+ fun initializeObjects() {
+ tree = AVLTree()
+ }
+
+ @Test
+ fun `validate tree if empty`() {
+ assertNull(tree.rootNode)
+ assertEquals(0, countNodes(tree.rootNode))
+ assertTrue(isAvl(tree.rootNode))
+ }
+
+ @Nested
+ inner class InsertionTests {
+ @Test
+ fun `insert a few key-value pairs`() {
+ tree.insert(2, 2)
+ tree.insert(3, 3)
+ tree.insert(1, 1)
+
+ assertEquals(2, tree.rootNode?.key)
+ assertEquals(3, tree.rootNode?.right?.key)
+ assertEquals(1, tree.rootNode?.left?.key)
+
+ assertEquals(3, countNodes(tree.rootNode))
+ assertTrue(isAvl(tree.rootNode))
+ }
+
+ @Test
+ fun `check left-left rotation case`() {
+ tree.insert(3, 3)
+ tree.insert(2, 2)
+ tree.insert(1, 1)
+
+ assertEquals(2, tree.rootNode?.key)
+ assertEquals(1, tree.rootNode?.left?.key)
+ assertEquals(3, tree.rootNode?.right?.key)
+
+ assertEquals(3, countNodes(tree.rootNode))
+ assertTrue(isAvl(tree.rootNode))
+ }
+
+ @Test
+ fun `check left-right rotation case`() {
+ tree.insert(5, 5)
+ tree.insert(3, 3)
+ tree.insert(4, 4)
+
+ assertEquals(4, tree.rootNode?.key)
+ assertEquals(3, tree.rootNode?.left?.key)
+ assertEquals(5, tree.rootNode?.right?.key)
+
+ assertEquals(3, countNodes(tree.rootNode))
+ assertTrue(isAvl(tree.rootNode))
+ }
+
+ @Test
+ fun `check right-right rotation case`() {
+ tree.insert(3, 3)
+ tree.insert(4, 4)
+ tree.insert(5, 5)
+
+ assertEquals(4, tree.rootNode?.key)
+ assertEquals(3, tree.rootNode?.left?.key)
+ assertEquals(5, tree.rootNode?.right?.key)
+
+ assertEquals(3, countNodes(tree.rootNode))
+ assertTrue(isAvl(tree.rootNode))
+ }
+
+ @Test
+ fun `check right-left rotation case`() {
+ tree.insert(3, 3)
+ tree.insert(5, 5)
+ tree.insert(4, 4)
+
+ assertEquals(4, tree.rootNode?.key)
+ assertEquals(3, tree.rootNode?.left?.key)
+ assertEquals(5, tree.rootNode?.right?.key)
+
+ assertEquals(3, countNodes(tree.rootNode))
+ assertTrue(isAvl(tree.rootNode))
+ }
+
+ @Test
+ fun `insert same key twice`() {
+ tree.insert(1, 1)
+ tree.insert(1, 2)
+ assertEquals(1, countNodes(tree.rootNode))
+ assertTrue(isAvl(tree.rootNode))
+ }
+
+ @Test
+ fun `insert many key-value pairs`() {
+ values.forEach { tree.insert(it, it) }
+ assertEquals(1000, countNodes(tree.rootNode))
+ assertTrue(isAvl(tree.rootNode))
+ }
+ }
+
+ @Nested
+ inner class FindTests {
+ @Test
+ fun `find a node by its key`() {
+ values.forEach { tree.insert(it, it) }
+ values.forEach { assertEquals(it, tree.find(it)) }
+ }
+
+ @Test
+ fun `find by non-existing key`() {
+ values.forEach { tree.insert(it, it) }
+ assertNull(tree.find(-1))
+ }
+ }
+
+ @Nested
+ inner class DeletionTests {
+ @Test
+ fun `delete one key-value pair`() {
+ tree.insert(1, 1)
+ tree.remove(1)
+ assertEquals(0, countNodes(tree.rootNode))
+ assertTrue(isAvl(tree.rootNode))
+ }
+
+ @Test
+ fun `delete non-existent key`() {
+ tree.insert(3, 3)
+ tree.insert(4, 4)
+ tree.insert(1, 1)
+ tree.remove(-1)
+ assertEquals(3, countNodes(tree.rootNode))
+ }
+
+ @Test
+ fun `delete many key-value pairs`() {
+ values.forEach { tree.insert(it, it) }
+ values.take(500).forEach { tree.remove(it) }
+ assertEquals(500, countNodes(tree.rootNode))
+ assertTrue(isAvl(tree.rootNode))
+ }
+ }
+}
diff --git a/trees/src/test/kotlin/bst/BstTest.kt b/trees/src/test/kotlin/bst/BstTest.kt
new file mode 100644
index 0000000..63013d2
--- /dev/null
+++ b/trees/src/test/kotlin/bst/BstTest.kt
@@ -0,0 +1,59 @@
+package bst
+
+import bst.nodes.BSTNode
+import org.junit.jupiter.api.Assertions.assertEquals
+import org.junit.jupiter.api.Assertions.assertNotEquals
+import org.junit.jupiter.api.Assertions.assertNull
+import org.junit.jupiter.api.Assertions.assertTrue
+import org.junit.jupiter.api.BeforeEach
+import org.junit.jupiter.api.Test
+
+class BstTest {
+ private fun , V> isBst(root: BSTNode?): Boolean {
+ if (root == null) {
+ return true
+ }
+ val left = root.left
+ val right = root.right
+ if ((left != null && left.key >= root.key) || (right != null && right.key <= root.key)) {
+ return false
+ }
+ return isBst(left) && isBst(right)
+ }
+
+ private fun , V> countNodes(node: BSTNode?): Int {
+ if (node == null) return 0
+ return countNodes(node.left) + countNodes(node.right) + 1
+ }
+
+ private lateinit var tree: BSTree
+
+ @BeforeEach
+ fun initializeObjects() {
+ tree = BSTree()
+ }
+
+ @Test
+ fun `validate tree if empty`() {
+ assertNull(tree.rootNode)
+ assertEquals(0, countNodes(tree.rootNode))
+ assertTrue(isBst(tree.rootNode))
+ }
+
+ @Test
+ fun `verify invariants after each action`() {
+ val values = IntArray(1000) { it + 1 }
+ values.shuffle()
+ values.forEach {
+ tree.insert(it, it)
+ assertTrue(isBst(tree.rootNode))
+ }
+ values.take(500).forEach {
+ tree.remove(it)
+ assertTrue(isBst(tree.rootNode))
+ }
+ values.takeLast(500).forEach {
+ assertNotEquals(null, tree.find(it))
+ }
+ }
+}
diff --git a/trees/src/test/kotlin/bst/RbtTest.kt b/trees/src/test/kotlin/bst/RbtTest.kt
new file mode 100644
index 0000000..b960b81
--- /dev/null
+++ b/trees/src/test/kotlin/bst/RbtTest.kt
@@ -0,0 +1,164 @@
+package bst
+
+import bst.nodes.RBTNode
+import org.junit.jupiter.api.Assertions.assertEquals
+import org.junit.jupiter.api.Assertions.assertNotEquals
+import org.junit.jupiter.api.Assertions.assertNull
+import org.junit.jupiter.api.BeforeEach
+import org.junit.jupiter.api.Nested
+import org.junit.jupiter.api.Test
+
+class RbtTest {
+ /*
+ This function makes sure that a tree is indeed red-black by walking over
+ every node and checking invariants. If it returns 0 that means
+ the tree is invalid red-black tree, and any other number is the black height
+ of the entire tree.
+ */
+ private fun , V> isRbt(root: RBTNode?): Int {
+ if (root == null) {
+ return 1
+ }
+ val left = root.left
+ val right = root.right
+ if (isRed(root)) {
+ if (isRed(left) && isRed(right)) {
+ return 0
+ }
+ }
+ val leftHeight = isRbt(left)
+ val rightHeight = isRbt(right)
+
+ // Invalid binary search tree
+ if ((left != null && left.key >= root.key) || (right != null && right.key <= root.key)) {
+ return 0
+ }
+
+ // Black height mismatch
+ if (leftHeight != 0 && rightHeight != 0 && leftHeight != rightHeight) {
+ return 0
+ }
+
+ // Counting black links
+ return if (leftHeight != 0 && rightHeight != 0) {
+ if (isRed(root)) leftHeight else leftHeight + 1
+ } else {
+ 0
+ }
+ }
+
+ private fun , V> isRed(node: RBTNode?): Boolean {
+ return node != null && node.color == RBTNode.Color.RED
+ }
+
+ private fun , V> countNodes(node: RBTNode?): Int {
+ if (node == null) return 0
+ return countNodes(node.left) + countNodes(node.right) + 1
+ }
+
+ private lateinit var tree: RedBlackTree
+ private val values = IntArray(1_000_000) { it + 1 }
+
+ @BeforeEach
+ fun initializeObjects() {
+ tree = RedBlackTree()
+ }
+
+ @Test
+ fun `validate tree if empty`() {
+ assertNull(tree.rootNode)
+ assertEquals(0, countNodes(tree.rootNode))
+ assertNotEquals(0, isRbt(tree.rootNode))
+ }
+
+ @Test
+ fun `verify invariants after each action`() {
+ values.take(1000).forEach {
+ tree.insert(it, it.toString())
+ assertNotEquals(0, isRbt(tree.rootNode))
+ }
+ values.take(500).forEach {
+ tree.remove(it)
+ assertNotEquals(0, isRbt(tree.rootNode))
+ }
+ assertEquals(500, countNodes(tree.rootNode))
+ }
+
+ @Nested
+ inner class InsertionTests {
+ @Test
+ fun `insert single key-value pair`() {
+ tree.insert(1, "A")
+ assertEquals(1, tree.rootNode?.key)
+ assertEquals(1, countNodes(tree.rootNode))
+ assertNotEquals(0, isRbt(tree.rootNode))
+ }
+
+ @Test
+ fun `insert a few key-value pairs`() {
+ tree.insert(19, "S")
+ tree.insert(5, "E")
+ tree.insert(1, "A")
+ tree.insert(18, "R")
+ assertEquals("E", tree.rootNode?.let { tree.find(it.key) })
+ assertEquals("A", tree.rootNode?.left?.let { tree.find(it.key) })
+ assertEquals(null, tree.find(10))
+
+ assertEquals(4, countNodes(tree.rootNode))
+ assertNotEquals(0, isRbt(tree.rootNode))
+ }
+
+ @Test
+ fun `insert same key twice`() {
+ tree.insert(1, "A")
+ tree.insert(1, "B")
+ assertEquals(1, countNodes(tree.rootNode))
+ assertNotEquals(0, isRbt(tree.rootNode))
+ assertEquals("B", tree.find(1))
+ }
+ }
+
+ @Nested
+ inner class DeleteTests {
+ @Test
+ fun `delete one key-value pair`() {
+ tree.insert(2, "B")
+ tree.remove(2)
+ assertEquals(0, countNodes(tree.rootNode))
+ assertNotEquals(0, isRbt(tree.rootNode))
+ }
+
+ @Test
+ fun `delete non-existent key-value pair`() {
+ tree.insert(2, "B")
+ tree.remove(3)
+ assertEquals(1, countNodes(tree.rootNode))
+ assertNotEquals(0, isRbt(tree.rootNode))
+ }
+
+ @Test
+ fun `delete a few key-value pairs`() {
+ tree.insert(19, "S")
+ tree.insert(5, "E")
+ tree.insert(1, "A")
+ tree.insert(18, "R")
+ tree.remove(1)
+ tree.remove(19)
+ assertEquals("R", tree.find(18))
+ assertEquals(null, tree.find(1))
+ tree.remove(18)
+ assertEquals("E", tree.find(5))
+ assertEquals(null, tree.find(18))
+ assertNotEquals(0, isRbt(tree.rootNode))
+ }
+
+ @Test
+ fun `delete many key-value pairs`() {
+ values.shuffle()
+ values.forEach { tree.insert(it, it.toString()) }
+ values.take(500_000).forEach { tree.remove(it) }
+ assertEquals(500_000, countNodes(tree.rootNode))
+ assertNotEquals(0, isRbt(tree.rootNode))
+ }
+ }
+}