Merge branch 'development' into initial-codefactor-suggested-improvem…

…ents

README.md

@@ -0,0 +1,29 @@
+# PADLA
+
+###### Plain And Direct Language Additions for Java
+
+[![License](https://img.shields.io/github/license/JarvisCraft/padla)](/LICENSE)
+[![CodeFactor](https://www.codefactor.io/repository/github/jarviscraft/padla/badge)](https://www.codefactor.io/repository/github/jarviscraft/padla)
+
+## What is it?
+
+PADLA is a collection of useful general-purpose utilities for Java aimed at fulfilling common needs.
+It uses functional approach intensively and attempts to follow OOP-approach as right as possible.
+In addition to common tools, it does also provide more specific ones aimed at maximal productivity.
+
+## Dependencies
+
+As its dependencies PADLA uses:
+- Compiletime:
+  - [Lombok](https://github.com/rzwitserloot/lombok) for generating boilerplate stuff
+  - [Jetbrains Annotations](https://github.com/JetBrains/java-annotations) and []() for documenting code logic
+- Runtime:
+  - [Guava](https://github.com/google/guava) for some general-purpose needs
+  - [GSON](https://github.com/google/gson) for manipulating JSON
+- Testing:
+  - [Junit5](https://github.com/junit-team/junit5/) with related sub-tools for testing
+  - [Hamcrest](https://github.com/hamcrest/JavaHamcrest) for more creating more readable tests
+  - [Mockito](https://github.com/mockito/mockito) for mocking in tests
+- Additional (these are not inherited by default and are required only if using specific classes):
+  - [ASM](https://gitlab.ow2.org/asm/asm) for runtime class generation (if using classes annotated with `BytecodeLibrary(ASM)`)
+  - [Javassist](https://github.com/jboss-javassist/javassist) for runtime class generation (if using classes annotated with `BytecodeLibrary(JAVASSIST)`)

java-commons/src/main/java/ru/progrm_jarvis/javacommons/lazy/Lazy.java

@@ -72,7 +72,7 @@ static <T> Lazy<T> createThreadSafe(@NonNull final Supplier<T> valueSupplier) {
      * @apiNote weak lazy stores the value wrapped in weak reference and so it may be GCed
      * and so the new one might be recomputed using the value supplier
      */
-    static <T> Lazy<T> createWeak(@NonNull final Supplier<T> valueSupplier) {
+    static <T> Lazy<T> createWeak(@NonNull final Supplier<@NotNull T> valueSupplier) {
         return new SimpleWeakLazy<>(valueSupplier);
     }
 
@@ -104,7 +104,7 @@ class SimpleLazy<T> implements Lazy<T> {
          */
         @Nullable Supplier<T> valueSupplier;
 
-        protected SimpleLazy(@NonNull final Supplier<T> valueSupplier) {
+        protected SimpleLazy(@SuppressWarnings("NullableProblems") @NonNull final Supplier<T> valueSupplier) {
             this.valueSupplier = valueSupplier;
         }
 
@@ -115,9 +115,10 @@ protected SimpleLazy(@NonNull final Supplier<T> valueSupplier) {
 
         @Override
         public T get() {
+            val valueSupplier = this.valueSupplier;
             if (valueSupplier != null) {
                 value = valueSupplier.get();
-                valueSupplier = null;
+                this.valueSupplier = null;
             }
 
             return value;
@@ -153,17 +154,21 @@ class DoubleCheckedLazy<T> implements Lazy<T> {
          */
         volatile T value;
 
-        protected DoubleCheckedLazy(@NonNull final Supplier<T> valueSupplier) {
+        protected DoubleCheckedLazy(@SuppressWarnings("NullableProblems") @NonNull final Supplier<T> valueSupplier) {
             mutex = new Object[0];
             this.valueSupplier = valueSupplier;
         }
 
         @Override
         public T get() {
             if (valueSupplier != null) synchronized (mutex) {
+                val valueSupplier = this.valueSupplier;
                 if (valueSupplier != null) {
-                    value = valueSupplier.get();
-                    valueSupplier = null;
+                    val value = this.value = valueSupplier.get();
+                    this.valueSupplier = null;
+
+                    // make sure no race is possible in theory
+                    return value;
                 }
             }
 

pom.xml

@@ -20,7 +20,7 @@
         <!-- Testing -->
         <version.junit>5.5.2</version.junit>
         <version.junit.platform>1.5.2</version.junit.platform>
-        <version.mockito>3.1.0</version.mockito>
+        <version.mockito>3.2.0</version.mockito>
     </properties>
 
     <name>PADLA for Java</name>