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Scala 3 and Data Sharing on Windows ↩

Dotty project Introduced in J2SE 5.0, Java class data sharing (CDS) helps reduce the startup time for Java applications as well as reduce their memory footprint.
This page presents findings from our experiments with CDS and Scala 3 on a Windows machine.

This document is part of a series of topics related to Scala 3 on Windows:

Ada, Akka, C++, Dart, Deno, Flix, Golang, GraalVM, Haskell, Kotlin, LLVM, Node.js, Rust, Spark, Spring, TruffleSqueak, WiX Toolset and Zig are other topics we are currently monitoring.

Project dependencies

This project depends on the following external software for the Microsoft Windows platform:

🔎 Scala 2.12 is a software product announced to require Java 8. In contrast Scala 2.13 and Scala 3 also support Java 9+. In the following we work with Temurin OpenJDK 11, the 2nd LTS version after Java 8.

For instance our development environment looks as follows (November 2024):

C:\opt\Git\                     (315 MB)
C:\opt\jdk-temurin-17.0.11_9\   (302 MB)
C:\opt\scala3-3.3.3\            ( 57 MB)

🔎 Git for Windows provides a BASH emulation used to run git from the command line (as well as over 250 Unix commands like awk, diff, file, grep, more, mv, rmdir, sed and wc).

Directory structure

This project is organized as follows:

bin\sharedata.bat
cdsexamples\DottyExample,JavaExample
CDS.md
setenv.bat

where

In the next sections we present both examples and describe the usage of command sharedata.

Java example

Source file src\main\java\Main.java is the main program of our Java code example:

package cdsexamples;
public class Main {
    public static void main(String[] args) {
        System.out.println("Hello from Java !");
        if (args.length > 0) {
            System.out.println(VMOptions.asString());
            //ScriptEngineTest.run();  // .jsa file size: 9 Mb -> 24 Mb !
        }
    }
}

Batch command build.bat has two new options working with the run subcommand:

  • Option -iter:<n> specifies the number of run iterations (for calculating meaningful average load times).
  • Option -share enables/disables data sharing.
> build help
Usage: build { <option> | <subcommand> }
 
  Options:
    -iter:<1..99>      set number of run iterations
    -share[:<on|off>]  enable/disable data sharing (default:off)
    -verbose           print progress messages
 
  Subcommands:
    clean              delete generated files
    compile            compile Java source files
    doc                generate Java documentation
    help               print this help message
    run[:<arg>]        execute main class with 1 optional argument

🔎 Internally the compile subcommand generates a Java archive and a Java shared archive as a last step of the compilation phase.

We first execute command build clean compile; the same command with option -verbose prints out the progress messages:

> build clean compile
 
> build -verbose clean compile
Delete output directory target
Create Java archive target\JavaExample.jar
Create class list file target\JavaExample.classlist
Create Java shared archive target\JavaExample.jsa

We can now execute our Java example without data sharing; the same command with option -verbose prints out the execution report:

> build run
Hello from Java !
 
> build run -verbose
Execute Java archive (#iterations=1) target\JavaExample.jar
Hello from Java !
Execution report:
   Share flag       : off
   Shared archive   : target\JavaExample.jsa
   Shared classes   : 0
   File classes     : 1
   jrt images       : 599
   Load time        : 0.108
   #iteration(s)    : 1
   Execution logs   : target\logs\log_share_off.log
Classes per package (600):
   java.io.* (38), java.lang.* (168), java.math.* (0), java.net.* (9)
   java.nio.* (38), java.security.* (24), java.util.* (137)
   jdk.* (111), scala.* (0), sun.* (74)
   [APP] cdsexamples.* (1)

🔎 Subcommand run accepts 1 optional argument for testing purposes; for instance build run:1 produces the following output (see src\main\java\VMOptions.java):

> build run:1
Hello from Java !
VM Options:
   -Xshare:off
   -XX:SharedArchiveFile=C:\<project_path>\target\JavaExample.jsa
   -Xlog:disable

Value for -Xlog is different with build run:1 -verbose:

   -Xlog:class+load:file=<project_path>\target\logs\log_share_on.log

We have submitted a bug report related to the usage of option -Xlog on Windows (see JDK-8215398); the bug was fixed on January 2, 2019.

For comparison here is the console output with data sharing; option -verbose prints out the execution report:

> build run -share
Hello from Java !
 
> build run -verbose -share
Execute Java archive (#iterations=1) target\JavaExample.jar
Hello from Java !
Execution report:
   Share flag       : on
   Shared archive   : target\JavaExample.jsa
   Shared classes   : 589
   File classes     : 0
   jrt images       : 1 (sun.nio.fs.WindowsLinkSupport source: jrt:/java.base)
   Load time        : 0.088
   #iteration(s)    : 1
   Execution logs   : target\logs\log_share_on.log
Classes per package (590):
   java.io.* (38), java.lang.* (168), java.math.* (0), java.net.* (9)
   java.nio.* (38), java.security.* (23), java.util.* (137)
   jdk.* (103), scala.* (0), sun.* (73)
   [APP] cdsexamples.* (1)

Subcommand run with option -iter:<n> (where n=1..99) executes the Java program n times:

> build run -verbose -share -iter:4
Execute Java archive (#iterations=4) target\JavaExample.jar
Hello from Java !
Hello from Java !
Hello from Java !
Hello from Java !
Execution report:
   Share flag       : on
   Shared archive   : target\JavaExample.jsa
   Shared classes   : 589
   File classes     : 0
   jrt images       : 1 (sun.nio.fs.WindowsLinkSupport source: jrt:/java.base)
   Average load time: 0.088s
   #iteration(s)    : 4
   Execution logs   : target\logs\log_share_on.log
Classes per package (590):
   java.io.* (38), java.lang.* (168), java.math.* (0), java.net.* (9)
   java.nio.* (38), java.security.* (23), java.util.* (137)
   jdk.* (103), scala.* (0), sun.* (73)
   [APP] cdsexamples.* (1)

Let's check the contents of the output directory target\:

> tree /a /f target | findstr /v "^[A-Z]"
|   JavaExample.classlist
|   JavaExample.jar
|   JavaExample.jsa
|   MANIFEST.MF
+---classes
|   |   .latest-build
|   \---cdsexamples
|           JavaExample.classs
|           ScriptEngineTest.class
|           VMOptions.class
\---logs
        log_classlist.log
        log_dump.log
        log_share_off.log
        log_share_on.log

Note the following about the generated files:

  • File MANIFEST.MF is added to JavaExample.jar as usual.
  • Files logs\log_classlist.log and logs\log_dump.log are generated when option -verbose is passed to the compile subcommand; they contain the execution logs for the generation of JavaExample.classlist resp. JavaExample.jsa.
  • File logs\log_share_off.log is generated when option -share:off is passed to the run subcommand.
  • File logs\log_share_on.log is generated when option -share:on is passed to the run subcommand.

For instance we can read from file logs\log_share_off.log that source of cdsexamples.Main is file:/ and that the total load time on the last line is 0.124s:

[0.008s][info][class,load] opened: c:\opt\jdk-temurin-17.0.9_9\lib\modules
[0.018s][info][class,load] java.lang.Object source: jrt:/java.base
[...]
[0.121s][info][class,load] cdsexamples.Main source: file:/<project_path>/target/JavaExample.jar
[...]
[0.124s][info][class,load] java.lang.Shutdown$Lock source: jrt:/java.base

We can also execute the java command (from Java 9+) directly to check if data sharing is effectively used:

> java -verbose:class -Xshare:on -XX:SharedArchiveFile=target\JavaExample.jsa ^
 -jar W:\cdsexamples\JavaExample\target\JavaExample.jar | findstr cdsexamples
[0.089s][info][class,load] cdsexamples.Main source: shared objects file

> java -verbose:class -Xshare:off -XX:SharedArchiveFile=target\JavaExample.jsa ^
 -jar W:\cdsexamples\JavaExample\target\JavaExample.jar | findstr cdsexamples
[0.112s][info][class,load] cdsexamples.Main source: file:/W:/dotty-examples/cdsexamples/JavaExample/target/Main.jar

⚠️ The crucial point here is to use the correct path of JavaExample.jar together with the specified Java shared archive. Command grep -a (-a means "process a binary file as if it were text") helps us to extract that path from JavaExample.jsa.

> grep -aPo '.{0,40}JavaExample.jar{0,40}' target\JavaExample.jsa
  W:\cdsexamples\JavaExample\target\JavaExample.jar
  W:\cdsexamples\JavaExample\target\JavaExample.jar

Scala 3 example ▴

Source file src\main\scala\Main.scala is the main program of our Scala 3 code example:

package cdsexamples
object Main {
  def main(args: Array[String]): Unit = {
    println("Hello from Scala 3 !")
    if (args.length > 0) {
      println(VMOptions.asString)
      //TastyTest.run()
    }
  }
}

Batch command build.bat has two new options working with the run subcommand:

  • Option -iter:<n> specifies the number of run iterations (for calculating meaningful average load times).
  • Option -share enables/disables data sharing.
> build help
Usage: build { <option> | <subcommand> }
 
  Options:
    -iter:<1..99>      set number of run iterations
    -share[:<on|off>]  enable/disable data sharing (default:off)
    -verbose           print progress messages
 
  Subcommands:
    clean              delete generated files
    compile            compile Scala source files
    doc                generate Scala documentation
    help               print this help message
    run[:<arg>]        execute main class with 1 optional argument

🔎 Internally the compile subcommand generates a Java archive and a Java shared archive as a last step of the compilation phase.

Similarly to the previous section we execute the following command; option -verbose prints out the progress messages:

> build clean compile
 
> build -verbose clean compile
Delete output directory target
Create Java archive target\DottyExample.jar
Create class list file target\DottyExample.classlist
Create Java shared archive target\DottyExample.jsa

We can now execute our Scala 3 example without data sharing (default settings: -share:off); option -verbose prints out the execution report:

> build run
Hello from Scala 3 !
 
> build run -verbose
Execute Java archive (#iterations=1) target\DottyExample.jar
Hello from Scala 3 !
Execution report:
   Share flag       : off
   Shared archive   : target\DottyExample.jsa
   Shared classes   : 0
   File classes     : 265
   jrt images       : 671
   Load time        : 0.355
   #iteration(s)    : 1
   Execution logs   : target\logs\log_share_off.log
Classes per package (940):
   java.io.* (39), java.lang.* (215), java.math.* (3), java.net.* (9)
   java.nio.* (38), java.security.* (24), java.util.* (142)
   jdk.* (125), sun.* (80)
   [APP] cdsexamples.* (2)
   scala.* (28), scala.collection.* (161), scala.compat.* (0)
   scala.io.* (1), scala.math.* (19), scala.reflect.* (25)
   scala.runtime.* (5), scala.sys.* (10), scala.util.* (14)

For comparison here is the output with data sharing; option -verbose prints out the execution report:

> build run -share
Hello from Scala 3 !
 
> build run -verbose -share
Execute Java archive (#iterations=1) target\DottyExample.jar
Hello from Scala 3 !
Execution report:
   Share flag       : on
   Shared archive   : target\DottyExample.jsa
   Shared classes   : 873
   File classes     : 0
   jrt images       : 1 (sun.nio.fs.WindowsLinkSupport source: jrt:/java.base)
   Load time        : 0.139
   #iteration(s)    : 1
   Execution logs   : target\logs\log_share_on.log
Classes per package (874):
   java.io.* (34), java.lang.* (207), java.math.* (3), java.net.* (9)
   java.nio.* (27), java.security.* (23), java.util.* (122)
   jdk.* (110), sun.* (74)
   [APP] cdsexamples.* (2)
   scala.* (28), scala.collection.* (161), scala.compat.* (0)
   scala.io.* (1), scala.math.* (19), scala.reflect.* (25)
   scala.runtime.* (5), scala.sys.* (10), scala.util.* (14)

Subcommand run with option -iter:<n> (n=1..99) executes n times the Scala 3 example:

> build run -verbose -share -iter:4
Execute Java archive (#iterations=4) target\DottyExample.jar
Hello from Scala 3 !
Hello from Scala 3 !
Hello from Scala 3 !
Hello from Scala 3 !
Execution report:
   Share flag       : on
   Shared archive   : target\DottyExample.jsa
   Shared classes   : 873
   File classes     : 0
   jrt images       : 1 (sun.nio.fs.WindowsLinkSupport source: jrt:/java.base)
   Average load time: 0.126s
   #iteration(s)    : 4
   Execution logs   : target\logs\log_share_on.log
Classes per package (874):
   java.io.* (34), java.lang.* (207), java.math.* (3), java.net.* (9)
   java.nio.* (27), java.security.* (23), java.util.* (122)
   jdk.* (110), sun.* (74)
   [APP] cdsexamples.* (2)
   scala.* (28), scala.collection.* (161), scala.compat.* (0)
   scala.io.* (1), scala.math.* (19), scala.reflect.* (25)
   scala.runtime.* (5), scala.sys.* (10), scala.util.* (14)

Finally we can check the contents of the output directory target\:

> tree /a /f target | findstr /v "^[A-Z]"
|   DottyExample.classlist
|   DottyExample.jar
|   DottyExample.jsa
|   MANIFEST.MF
+---classes
|   |   .latest-build
|   \---cdsexamples
|           Main$.class
|           Main.class
|           Main.tasty
|           TastyTest$.class
|           TastyTest.class
|           TastyTest.tasty
|           VMOptions$.class
|           VMOptions.class
|           VMOptions.tasty
\---logs
        log_classlist.log
        log_dump.log
        log_share_off.log
        log_share_on.log

Note the following about the generated files:

  • File MANIFEST.MF is added to DottyExample.jar as usual.
  • Files classes\Main$.class and classes\Main.tasty (typed AST) are specific to the Scala 3 compiler.
  • Files logs\log_classlist.log and logs\log_dump.log are generated when option -verbose is passed to the compile subcommand; they contain the execution logs for the generation of DottyExample.classlist resp. DottyExample.jsa.
  • File logs\log_share_off.log is generated when option -share:off is passed to the run subcommand.
  • File logs\log_share_on.log is generated when option -share:on is passed to the run subcommand.

Batch command sharedata ▴

Command sharedata creates and (un-)installs Java shared archives for both scala and scalac:

> sharedata help
Usage: sharedata { <option> | <subcommand> }
 
  Options:
    -share[:<on|off>]  set the share flag (default:off)
    -verbose           print progress messages
  Subcommands:
    activate           install the Java shared archive
    dump               create the Java shared archive
    help               print this help message
    reset              uninstall the Java shared archive
    test               execute test application (depends on dump)

> sharedata activate
Create class list file out\data-sharing\dotty-cds-compiler.classlist
Create Java shared archive out\data-sharing\dotty-cds-compiler.jsa
Create class list file out\data-sharing\dotty-cds-repl.classlist
Create Java shared archive out\data-sharing\dotty-cds-repl.jsa
Support files for Java class sharing:
   dotty-cds-compiler.classlist (119 Kb)
   dotty-cds-compiler.jsa (55616 Kb)
   dotty-cds-repl.classlist (31 Kb)
   dotty-cds-repl.jsa (16640 Kb)
   dotty-cds_0.27-0.27.0-RC1.jar (3 Kb)

> dir /b c:\opt\scala3_3.3.3\lib\dotty-cds*
dotty-cds-compiler.classlist
dotty-cds-compiler.jsa
dotty-cds-repl.classlist
dotty-cds-repl.jsa
dotty-cds_3-3.3.3.jar

package cds
object Main {
  def main(args: Array[String]): Unit = {
    println("Support files for Java class sharing:")
    val jarUrl = getClass().getProtectionDomain().getCodeSource().getLocation()
    val libDir = java.nio.file.Paths.get(jarUrl.toURI()).getParent().toFile()
    val files = libDir.listFiles.filter(_.getName.startsWith("dotty-cds"))
    files.foreach(f => println("   "+f.getName()+" ("+(f.length()/1024)+" Kb)"))
  }
}

Subcommand test ...tbd...; option -verbose prints out the execution report:

> sharedata test
Support files for Java class sharing:
   dotty-cds-compiler.classlist (119 Kb)
   dotty-cds-compiler.jsa (55616 Kb)
   dotty-cds-repl.classlist (31 Kb)
   dotty-cds-repl.jsa (16640 Kb)
   dotty-cds_0.27-0.27.0-RC1.jar (3 Kb)
 
> sharedata -verbose test
Execute test application with Scala REPL WITHOUT Java shared archive
Support files for Java class sharing:
   dotty-cds-compiler.classlist (120 Kb)
   dotty-cds-compiler.jsa (56832 Kb)
   dotty-cds-repl.classlist (31 Kb)
   dotty-cds-repl.jsa (16640 Kb)
   dotty-cds_0.27-0.27.0-RC1.jar (4 Kb)
Execution report:
   Share flag      : off
   Shared archive  : out\data-sharing\dotty-cds-repl.jsa
   Shared classes  : 0
   File classes    : 274
   jrt images      : 680
   Load time       : 0.386s
   Execution logs  : out\data-sharing\logs\dotty-cds-repl-share.log
Classes per package (949):
   java.io.* (41), java.lang.* (218), java.net.* (9), java.nio.* (41)
   java.security.* (24), java.util.* (142), jdk.* (121), sun.* (81)
   [APP] cds.* (2)
   scala.* (28), scala.collection.* (165), scala.compat.* (0)
   scala.io.* (1), scala.math.* (19), scala.reflect.* (27)
   scala.runtime.* (6), scala.sys.* (10), scala.util.* (14)

> sharedata -verbose -share test
Execute test application with Scala REPL WITH Java shared archive
Support files for Java class sharing:
   dotty-cds-compiler.classlist (119 Kb)
   dotty-cds-compiler.jsa (55616 Kb)
   dotty-cds-repl.classlist (31 Kb)
   dotty-cds-repl.jsa (16640 Kb)
   dotty-cds_0.27-0.27.0-RC1.jar (3 Kb)
Execution report:
   Share flag      : on
   Shared archive  : out\data-sharing\dotty-cds-repl.jsa
   Shared classes  : 887
   File classes    : 0
   jrt images      : 1 (sun.nio.fs.WindowsLinkSupport source: jrt:/java.base)
   Load time       : 0.140s
   Execution logs  : out\data-sharing\logs\dotty-cds-repl-share.log
Classes per package (888):
   java.io.* (36), java.lang.* (210), java.net.* (9), java.nio.* (30)
   java.security.* (23), java.util.* (122), jdk.* (106), sun.* (75)
   [APP] cds.* (2)
   scala.* (28), scala.collection.* (165), scala.compat.* (0)
   scala.io.* (1), scala.math.* (19), scala.reflect.* (27)
   scala.runtime.* (6), scala.sys.* (10), scala.util.* (14)

☛ Data Sharing and Oracle OpenJDK 11
The Oracle OpenJDK 11 installation contains the file <install_dir>\lib\classlist. Let's check if data sharing is enabled:

  1. Command java.exe -version displays the OpenJDK version amongst other information; in particular, the last displayed line ends with (build 11.0.20+8, mixed mode, sharing) if data sharing is enabled, with (build 11.0.20+8, mixed mode) otherwise.
  2. Command java.exe -Xshare:dump generates the 17.3 Mb Java shared archive <install_dir>\bin\server\classes.jsa from file <install_dir>\lib\classlist.
  3. Repeat command from point 1.
> c:\opt\jdk-temurin-11.0.20_8\bin\java -version
openjdk version "11.0.20" 2023-07-18
OpenJDK Runtime Environment Temurin-11.0.19+7 (build 11.0.19+7)
OpenJDK 64-Bit Server VM Temurin-11.0.19+7 (build 11.0.19+7, mixed mode)
 
> c:\opt\jdk-temurin-11.0.17_8\bin\java -Xshare:dump
[...]
Number of classes 1272
[...]
mc  space:      8416 [  0.0% of total] [...]
rw  space:   4022976 [ 22.2% of total] [...]
ro  space:   7305216 [ 40.4% of total] [...]
md  space:      2560 [  0.0% of total] [...]
od  space:   6534648 [ 36.1% of total] [...]
total    :  17873816 [100.0% of total] [...]
 
> dir /b c:\opt\jdk-temurin-11.0.20_8\bin\server
classes.jsa
jvm.dll
 
> c:\opt\jdk-temurin-11.0.20_8\bin\java -version
openjdk version "11.0.20" 2023-07-18
OpenJDK Runtime Environment Temurin-11.0.20+8 (build 11.0.20+8)
OpenJDK 64-Bit Server VM Temurin-11.0.20+8 (build 11.0.20+8, mixed mode, sharing)

Java 12 introduces default CDS archives (JEP 341) to improve out-of-the-box startup time and to get rid of the need to run -Xshare: dump to benefit from the CDS.

Usage example ▴

> cd examples\enum-Planet
> scalac -share -d target\classes src\main\scala\Planet.scala "-J-Xlog:class+load=info" > class-load.txt

We can observe that 24 classes could not be found in the Java shared archive dotty-cds-compiler.jsa:

> findstr /c:"source: file" class-load.txt
[0.761s][info][class,load] dotty.tools.dotc.core.Comments$Comment$ source: file:/C:/opt/dotty-0.27.0-RC1/lib/dotty-compiler_0.27-0.27.0-RC1.jar
[0.766s][info][class,load] dotty.tools.dotc.ast.untpd$Mod$ source: file:/C:/opt/dotty-0.27.0-RC1/lib/dotty-compiler_0.27-0.27.0-RC1.jar
[0.766s][info][class,load] dotty.tools.dotc.ast.untpd$Mod$Enum$ source: file:/C:/opt/dotty-0.27.0-RC1/lib/dotty-compiler_0.27-0.27.0-RC1.jar
[0.771s][info][class,load] dotty.tools.dotc.ast.untpd$Mod$Private$ source: file:/C:/opt/dotty-0.27.0-RC1/lib/dotty-compiler_0.27-0.27.0-RC1.jar
[0.772s][info][class,load] dotty.tools.dotc.ast.untpd$Mod$Final$ source: file:/C:/opt/dotty-0.27.0-RC1/lib/dotty-compiler_0.27-0.27.0-RC1.jar
[0.782s][info][class,load] dotty.tools.dotc.parsing.xml.Utility$ source: file:/C:/opt/dotty-0.27.0-RC1/lib/dotty-compiler_0.27-0.27.0-RC1.jar
[0.783s][info][class,load] dotty.tools.dotc.ast.untpd$GenFrom$ source: file:/C:/opt/dotty-0.27.0-RC1/lib/dotty-compiler_0.27-0.27.0-RC1.jar

[0.783s][info][class,load] dotty.tools.dotc.ast.untpd$ForDo$ source: file:/C:/opt/dotty-0.27.0-RC1/lib/dotty-compiler_0.27-0.27.0-RC1.jar
[0.784s][info][class,load] dotty.tools.dotc.ast.untpd$InterpolatedString$ source: file:/C:/opt/dotty-0.27.0-RC1/lib/dotty-compiler_0.27-0.27.0-RC1.jar
[0.979s][info][class,load] dotty.tools.dotc.ast.DesugarEnums$CaseKind$ source: file:/C:/opt/dotty-0.27.0-RC1/lib/dotty-compiler_0.27-0.27.0-RC1.jar
[0.988s][info][class,load] dotty.tools.dotc.typer.ProtoTypes$PolyProto$ source: file:/C:/opt/dotty-0.27.0-RC1/lib/dotty-compiler_0.27-0.27.0-RC1.jar
[1.101s][info][class,load] dotty.tools.dotc.core.Types$RecType$ source: file:/C:/opt/dotty-0.27.0-RC1/lib/dotty-compiler_0.27-0.27.0-RC1.jar
[1.349s][info][class,load] dotty.tools.dotc.ast.desugar$IdPattern$ source: file:/C:/opt/dotty-0.27.0-RC1/lib/dotty-compiler_0.27-0.27.0-RC1.jar
[1.407s][info][class,load] scala.collection.mutable.ListBuffer$$anon$1 source: file:/C:/opt/dotty-0.27.0-RC1/lib/scala-library-2.13.0.jar
[1.464s][info][class,load] dotty.tools.dotc.ast.Trees$Import$ source: file:/C:/opt/dotty-0.27.0-RC1/lib/dotty-compiler_0.27-0.27.0-RC1.jar [1.473s][info][class,load] dotty.tools.dotc.ast.Trees$Typed$ source: file:/C:/opt/dotty-0.27.0-RC1/lib/dotty-compiler_0.27-0.27.0-RC1.jar
[1.479s][info][class,load] dotty.tools.dotc.ast.Trees$SeqLiteral$ source: file:/C:/opt/dotty-0.27.0-RC1/lib/dotty-compiler_0.27-0.27.0-RC1.jar
[1.574s][info][class,load] scala.runtime.java8.JFunction1$mcZI$sp source: file:/C:/opt/dotty-0.27.0-RC1/lib/scala-library-2.13.0.jar
[1.821s][info][class,load] dotty.tools.dotc.core.NameOps$TermNameDecorator$ source: file:/C:/opt/dotty-0.27.0-RC1/lib/dotty-compiler_0.27-0.27.0-RC1.jar
[1.842s][info][class,load] dotty.tools.dotc.ast.Trees$Assign$ source: file:/C:/opt/dotty-0.27.0-RC1/lib/dotty-compiler_0.27-0.27.0-RC1.jar [1.928s][info][class,load] dotty.tools.backend.jvm.BCodeAsmCommon$EnclosingMethodEntry source: file:/C:/opt/dotty-0.27.0-RC1/lib/dotty-compiler_0.27-0.27.0-RC1.jar
[2.075s][info][class,load] scala.transient source: file:/C:/opt/dotty-0.27.0-RC1/lib/scala-library-2.13.0.jar
[2.076s][info][class,load] scala.volatile source: file:/C:/opt/dotty-0.27.0-RC1/lib/scala-library-2.13.0.jar

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2019

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2018

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mics/November 2024 ▲