This repository gathers Akka code examples coming from various websites and books. It also includes several build scripts (Ant files, bash scripts, batch files, Make scripts) for experimenting with Akka on a Windows machine.

Ada, C++, COBOL, Dafny, Dart, Deno, Docker, Flix, Go, GraalVM, Haskell, Kafka, Kotlin, LLVM, Modula-2, Node.js, Rust, Scala 3, Spark, Spring, Standard ML, TruffleSqueak, WiX Toolset and Zig are other topics we are continuously investigating.

☛ Read the document "What is Akka?" from the Akka Guide for a quick overview of the Akka toolkit.

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

• Git 2.47 (release notes)
• Scala 2.13 (requires Java 8+) (release notes)
• Temurin OpenJDK 17 LTS (release notes, bug fixes)

☛ Maven packages
We present the Maven package dependencies in document PACKAGES.md.

Optionally one may also install the following software:

• Apache Ant 1.10 (requires Java 8+) (release notes)
• Apache Maven 3.9 (requires Java 8+) (release notes)
• ConEmu 2023 (release notes)
• GNU Make 3.81
• Gradle 8.12 ¹ (requires Java 8+) (release notes)
• grpcurl 1.9 (release notes)
• sbt 1.10 (requires Java 8+) (release notes)
• Scala 3.3 LTS (release notes)
• Temurin OpenJDK 21 LTS ¹ (release notes, Java 21 API)
• Visual Studio Code 1.96 (release notes)

🔎 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).

For instance our development environment looks as follows (January 2025) ²:

C:\opt\apache-ant\              ( 43 MB)
C:\opt\apache-maven\            ( 10 MB)
C:\opt\ConEmu\                  ( 26 MB)
C:\opt\Git\                     (387 MB)
C:\opt\gradle\                  (144 MB)
C:\opt\grpcurl\                 ( 24 MB)
C:\opt\jdk-temurin-17.0.13.11\  (304 MB)
C:\opt\jdk-temurin-21.0.5_11\   (329 MB)
C:\opt\make-3.81\               (  2 MB)
C:\opt\sbt\                     (110 MB)
C:\opt\scala-2.13.15\           ( 25 MB)
C:\opt\scala3-3.3.5\            ( 38 MB)
C:\opt\VSCode\                  (341 MB)

☛ Installation policy
When possible we install software from a Zip archive rather than via a Windows installer. In our case we defined C:\opt\ as the installation directory for optional software tools (in reference to the /opt/ directory on Unix).

This project is organized as follows:

bin\
alexandreesl-examples\{README.md, akka-stream-lab}
akka\     (Git submodule)
akka-concurrency\{README.md, Avionics, BadSharespearean, etc.}
akka-cookbook\{README.md, HelloAkka, PriorityMailbox, etc.}
akka-essentials\{README.md, FirstAkkaApplication, etc.}
docs\
effective-akka\{README.md, ExtraPattern, etc.>}
examples\{README.md, akka-quickstart-java, akka-quickstart-kotlin, ..}
pekko-examples\{README.md, HelloWorld, etc.>}
PACKAGES.md
README.md
RESOURCES.md
setenv.bat

where

• directory bin\ provides several utility batch files
• directory alexandreesl-examples\ contains Akka code examples from Alexandre's blog post.
• directory akka\ contains our fork of the akka/akka repository as a Github submodule.
• directory akka-concurrency\ contains Akka code examples from Wyatt's book.
• directory akka-cookbook\ contains Akka code examples from Ortiz's book.
• directory akka-essentials\ contains Akka code examples from Gupta's book.
• directory docs\ contains Akka related papers/articles.
• directory effective-akka\ contains Akka code examples from Allen's book.
• directory examples\ contains Akka examples grabbed from various websites (see file examples\README.md).
• directory pekko-examples\ contains Akka code examples from the Pekko project.
• file PACKAGES.md presents the Maven packages our projects depend on.
• file README.md is the Markdown document for this page.
• file RESOURCES.md is the Markdown document presenting external resources.
• file setenv.bat is the batch command for setting up our environment.

We execute command setenv.bat once to setup our development environment; it makes external tools such as ant.bat, git.exe or sbt.bat directly available from the command prompt.

> setenv
Tool versions:
   javac 17.0.13, scalac 2.13.15, sbt 1.10.7,
   ant 1.10.15, gradle 8.12, mvn 3.9.9, grpcurl v1.9.2,
   make 3.81, git 2.47.1, diff 3.10, bash 5.2.37(1)

> where ant git sbt
C:\opt\apache-ant\bin\ant
C:\opt\apache-ant\bin\ant.bat
C:\opt\apache-ant\bin\ant.cmd
C:\opt\Git\bin\git.exe
C:\opt\Git\mingw64\bin\git.exe
C:\opt\sbt\bin\sbt
C:\opt\sbt\bin\sbt.bat

Command searchjars.bat prints the list of all JAR files containing a specific class or method name among the locally available libraries. In the following example we search for occurrences of class NotUsed :

> searchjars.bat NotUsed
Warning: Search all directories (no option specified)
Searching for class "NotUsed" in files "C:\opt\scala3-3.3.5\lib\*.jar"
Searching for class "NotUsed" in files "C:\opt\scala-2.13.15\lib\*.jar"
Searching for class "NotUsed" in files "C:\opt\jdk-temurin-17.0.13.11\lib\*.jar"
Searching for class "NotUsed" in files "%USERPROFILE%\.ivy2\cache\*.jar"
  akka-actor_2.13-2.10.0.jar:akka/NotUsed$.class
  akka-actor_2.13-2.10.0.jar:akka/NotUsed.class
Searching for class "NotUsed" in files "%USERPROFILE%\.m2\repository\*.jar"
  akka-actor_2.13-2.10.0.jar:akka/NotUsed$.class
  akka-actor_2.13-2.10.0.jar:akka/NotUsed.class
  akka-stream_2.13-2.10.0.jar:akka/stream/impl/PushNotUsed$.class
  akka-stream_2.13-2.10.0.jar:akka/stream/impl/PushNotUsed.class
  pekko-actor_2.13-1.0.3.jar:org/apache/pekko/NotUsed$.class
  pekko-actor_2.13-1.0.3.jar:org/apache/pekko/NotUsed.class

[1] Gradle Support for Java ↩

Gradle version	Java version
8.11, 8.12	23
8.10	23
8.9	22
8.7, 8.8	22
8.4, 8.5, 8.6	21
8.3	20
7.6, 8.0 a), 8.1, 8.2	19
7.5	18
7.3	17
7.0	16
6.7	15
6.3	14
6.0	13

^a) Version 8.0.2 or newer is required for use with Scala 2.13 (see issue 23962).

[2] Downloads ↩

In our case we downloaded the following installation files (see section 1):

apache-ant-1.10.15-bin.zip                         (  9 MB)
apache-maven-3.9.9-bin.zip                         ( 10 MB)
ConEmuPack.230724.7z                               (  5 MB)
gradle-8.12-bin.zip                                (130 MB)
grpcurl_1.9.2_windows_x86_64.zip                   (  6 MB)
make-3.81-bin.zip                                  ( 10 MB)
OpenJDK17U-jdk_x64_windows_hotspot_17.0.13.11.zip  (188 MB)
OpenJDK21U-jdk_x64_windows_hotspot_21.0.5_11.zip   (191 MB)
PortableGit-2.47.1-64-bit.7z.exe                   ( 47 MB)
sbt-1.10.7.zip                                     ( 45 MB)
scala-2.13.15.zip                                  ( 21 MB)
scala3-3.3.5-RC1.zip                               ( 34 MB)
VSCode-win32-x64-1.96.2.zip                        (131 MB)

[3] setenv.bat usage ↩

Batch file setenv.bat has specific environment variables set that enable us to use command-line developer tools more easily.

It is similar to the setup scripts described on the page "Visual Studio Developer Command Prompt and Developer PowerShell" of the Visual Studio online documentation.

For instance we can quickly check that the two scripts Launch-VsDevShell.ps1 and VsDevCmd.bat are indeed available in our Visual Studio 2019 installation :

> where /r "C:\Program Files (x86)\Microsoft Visual Studio" *vsdev*
C:\Program Files (x86)\Microsoft Visual Studio\2019\Community\Common7\Tools\Launch-VsDevShell.ps1
C:\Program Files (x86)\Microsoft Visual Studio\2019\Community\Common7\Tools\VsDevCmd.bat
C:\Program Files (x86)\Microsoft Visual Studio\2019\Community\Common7\Tools\vsdevcmd\core\vsdevcmd_end.bat
C:\Program Files (x86)\Microsoft Visual Studio\2019\Community\Common7\Tools\vsdevcmd\core\vsdevcmd_start.bat

Concretely, in our GitHub projects which depend on Visual Studio (e.g. michelou/cpp-examples), setenv.bat does invoke VsDevCmd.bat (resp. vcvarall.bat for older Visual Studio versions) to setup the Visual Studio tools on the command prompt.

mics/January 2025 ▲