Bumped samples Java 22 and Gradle 8.8

.github/workflows/samples_distributed-processes.yml

@@ -23,7 +23,7 @@ jobs:
     strategy:
       # define the test matrix
       matrix:
-        java-version: [21]
+        java-version: [22]
 
     steps:
       - name: Check Out Repo

.github/workflows/samples_event-sourcing-esdb-aggregates.yml

@@ -23,7 +23,7 @@ jobs:
     strategy:
       # define the test matrix
       matrix:
-        java-version: [21]
+        java-version: [22]
 
     steps:
       - name: Check Out Repo

.github/workflows/samples_event-sourcing-esdb-simple.yml

@@ -23,7 +23,7 @@ jobs:
     strategy:
       # define the test matrix
       matrix:
-        java-version: [21]
+        java-version: [22]
 
     steps:
       - name: Check Out Repo

.github/workflows/samples_event-stream-metadata.yml

@@ -23,7 +23,7 @@ jobs:
     strategy:
       # define the test matrix
       matrix:
-        java-version: [21]
+        java-version: [22]
 
     steps:
       - name: Check Out Repo

.github/workflows/samples_events-versioning.yml

@@ -23,7 +23,7 @@ jobs:
     strategy:
       # define the test matrix
       matrix:
-        java-version: [21]
+        java-version: [22]
 
     steps:
       - name: Check Out Repo

.github/workflows/samples_uniqueness.yml

@@ -23,7 +23,7 @@ jobs:
     strategy:
       # define the test matrix
       matrix:
-        java-version: [21]
+        java-version: [22]
 
     steps:
       - name: Check Out Repo

README.md

@@ -14,6 +14,7 @@ Tutorial, practical samples and other resources about Event Sourcing in JVM. See
     - [Event Store](#event-store)
   - [Videos](#videos)
     - [Practical introduction to Event Sourcing with Spring Boot and EventStoreDB](#practical-introduction-to-event-sourcing-with-spring-boot-and-eventstoredb)
+    - [Facts and Myths about CQRS](#facts-and-myths-about-cqrs)
     - [Let's build the worst Event Sourcing system!](#lets-build-the-worst-event-sourcing-system)
     - [The Light and The Dark Side of the Event-Driven Design](#the-light-and-the-dark-side-of-the-event-driven-design)
     - [Conversation with Yves Lorphelin about CQRS](#conversation-with-yves-lorphelin-about-cqrs)
@@ -293,7 +294,7 @@ The presented use case is Shopping Cart flow:
 5. The customer may also cancel the shopping cart and reject all selected products.
 6. After shopping cart confirmation or cancellation, the product can no longer be added or removed from the cart.
 
-Technically it's modelled as Web API written in [Spring Boot](https://spring.io/projects/spring-boot) and [Java 17](https://www.oracle.com/java/technologies/downloads/). 
+Technically it's modelled as Web API written in [Spring Boot](https://spring.io/projects/spring-boot) and [Java 22](https://www.oracle.com/java/technologies/downloads/). 
 
 There are two variations of those samples:
 - [Event Sourcing with Spring Boot and EventStoreDB](./samples/event-sourcing-esdb-simple)
@@ -312,7 +313,7 @@ There are two variations of those samples:
 
 For running the Event Store examples you need to have:
 
-1. Java JDK 17 (or later) installed - https://www.oracle.com/java/technologies/downloads/.
+1. Java JDK 22 (or later) installed - https://www.oracle.com/java/technologies/downloads/.
 2. Installed IntelliJ, Eclipse, VSCode or other preferred IDE.
 3. [Docker](https://store.docker.com/search?type=edition&offering=community) installed.
 

samples/distributed-processes/build.gradle

@@ -4,7 +4,7 @@ plugins {
 
 java {
   toolchain {
-    languageVersion = JavaLanguageVersion.of(21)
+    languageVersion = JavaLanguageVersion.of(22)
   }
 }
 

samples/distributed-processes/gradle/wrapper/gradle-wrapper.properties

@@ -1,5 +1,7 @@
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-8.7-bin.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-8.8-rc-1-bin.zip
+networkTimeout=10000
+validateDistributionUrl=true
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists

samples/distributed-processes/gradlew

@@ -55,7 +55,7 @@
 #       Darwin, MinGW, and NonStop.
 #
 #   (3) This script is generated from the Groovy template
-#       https://github.com/gradle/gradle/blob/master/subprojects/plugins/src/main/resources/org/gradle/api/internal/plugins/unixStartScript.txt
+#       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/.
@@ -80,13 +80,11 @@ do
     esac
 done
 
-APP_HOME=$( cd "${APP_HOME:-./}" && pwd -P ) || exit
-
-APP_NAME="Gradle"
+# This is normally unused
+# shellcheck disable=SC2034
 APP_BASE_NAME=${0##*/}
-
-# 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"'
+# Discard cd standard output in case $CDPATH is set (https://github.com/gradle/gradle/issues/25036)
+APP_HOME=$( cd "${APP_HOME:-./}" > /dev/null && pwd -P ) || exit
 
 # Use the maximum available, or set MAX_FD != -1 to use that value.
 MAX_FD=maximum
@@ -133,22 +131,29 @@ 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.
+    if ! command -v java >/dev/null 2>&1
+    then
+        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
 fi
 
 # Increase the maximum file descriptors if we can.
 if ! "$cygwin" && ! "$darwin" && ! "$nonstop" ; then
     case $MAX_FD in #(
       max*)
+        # In POSIX sh, ulimit -H is undefined. That's why the result is checked to see if it worked.
+        # shellcheck disable=SC2039,SC3045
         MAX_FD=$( ulimit -H -n ) ||
             warn "Could not query maximum file descriptor limit"
     esac
     case $MAX_FD in  #(
       '' | soft) :;; #(
       *)
+        # In POSIX sh, ulimit -n is undefined. That's why the result is checked to see if it worked.
+        # shellcheck disable=SC2039,SC3045
         ulimit -n "$MAX_FD" ||
             warn "Could not set maximum file descriptor limit to $MAX_FD"
     esac
@@ -193,18 +198,28 @@ if "$cygwin" || "$msys" ; then
     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.
+
+# 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"'
+
+# Collect all arguments for the java command:
+#   * DEFAULT_JVM_OPTS, JAVA_OPTS, JAVA_OPTS, and optsEnvironmentVar are not allowed to contain shell fragments,
+#     and any embedded shellness will be escaped.
+#   * For example: A user cannot expect ${Hostname} to be expanded, as it is an environment variable and will be
+#     treated as '${Hostname}' itself on the command line.
 
 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.

samples/distributed-processes/gradlew.bat

@@ -14,7 +14,7 @@
 @rem limitations under the License.
 @rem
 
-@if "%DEBUG%" == "" @echo off
+@if "%DEBUG%"=="" @echo off
 @rem ##########################################################################
 @rem
 @rem  Gradle startup script for Windows
@@ -25,7 +25,8 @@
 if "%OS%"=="Windows_NT" setlocal
 
 set DIRNAME=%~dp0
-if "%DIRNAME%" == "" set DIRNAME=.
+if "%DIRNAME%"=="" set DIRNAME=.
+@rem This is normally unused
 set APP_BASE_NAME=%~n0
 set APP_HOME=%DIRNAME%
 
@@ -40,13 +41,13 @@ if defined JAVA_HOME goto findJavaFromJavaHome
 
 set JAVA_EXE=java.exe
 %JAVA_EXE% -version >NUL 2>&1
-if "%ERRORLEVEL%" == "0" goto execute
+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.
+echo. 1>&2
+echo ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH. 1>&2
+echo. 1>&2
+echo Please set the JAVA_HOME variable in your environment to match the 1>&2
+echo location of your Java installation. 1>&2
 
 goto fail
 
@@ -56,11 +57,11 @@ 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.
+echo. 1>&2
+echo ERROR: JAVA_HOME is set to an invalid directory: %JAVA_HOME% 1>&2
+echo. 1>&2
+echo Please set the JAVA_HOME variable in your environment to match the 1>&2
+echo location of your Java installation. 1>&2
 
 goto fail
 
@@ -75,13 +76,15 @@ set CLASSPATH=%APP_HOME%\gradle\wrapper\gradle-wrapper.jar
 
 :end
 @rem End local scope for the variables with windows NT shell
-if "%ERRORLEVEL%"=="0" goto mainEnd
+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!
-if  not "" == "%GRADLE_EXIT_CONSOLE%" exit 1
-exit /b 1
+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

samples/event-sourcing-esdb-aggregates/README.md

@@ -14,7 +14,7 @@ The presented use case is Shopping Cart flow:
 5. The customer may also cancel the shopping cart and reject all selected products.
 6. After shopping cart confirmation or cancellation, the product can no longer be added or removed from the cart.
 
-Technically it's modelled as Web API written in [Spring Boot](https://spring.io/projects/spring-boot) and [Java 17](https://www.oracle.com/java/technologies/downloads/). 
+Technically it's modelled as Web API written in [Spring Boot](https://spring.io/projects/spring-boot) and [Java 22](https://www.oracle.com/java/technologies/downloads/). 
 
 ## Watch the video
 
@@ -41,7 +41,7 @@ It uses:
 - App has Swagger and predefined [docker-compose](./docker-compose.yml) to run and play with samples.
 
 ## Write Model
-- Sample [ShoppingCart](./src/main/java/io/eventdriven/ecommerce/shoppingcarts/ShoppingCart.java) aggregate and [events](./src/main/java/io/eventdriven/ecommerce/shoppingcarts/ShoppingCartEvent.java) represent the business workflow. All events are stored in the same file using [sealed classes](https://blogs.oracle.com/javamagazine/post/java-sealed-classes-fight-ambiguity) to be able to understand flow without jumping from one file to another. It also enables better typing support in pattern matching. `ShoppingCart` also contains [when method](./src/main/java/io/eventdriven/ecommerce/shoppingcarts/ShoppingCart.java#L113) method defining how to apply events to get the entity state. It uses the Java 17 switch syntax for pattern matching.
+- Sample [ShoppingCart](./src/main/java/io/eventdriven/ecommerce/shoppingcarts/ShoppingCart.java) aggregate and [events](./src/main/java/io/eventdriven/ecommerce/shoppingcarts/ShoppingCartEvent.java) represent the business workflow. All events are stored in the same file using [sealed classes](https://blogs.oracle.com/javamagazine/post/java-sealed-classes-fight-ambiguity) to be able to understand flow without jumping from one file to another. It also enables better typing support in pattern matching. `ShoppingCart` also contains [when method](./src/main/java/io/eventdriven/ecommerce/shoppingcarts/ShoppingCart.java#L113) method defining how to apply events to get the entity state. It uses the Java 22 switch syntax for pattern matching.
 - business logic is encapsulated into aggregate methods. It helps to keep the invariants and business logic in the same place. They are pure functions that take command and/or state and create new events based on the business logic. See sample [Adding Product Item to ShoppingCart](./src/main/java/io/eventdriven/ecommerce/shoppingcarts/ShoppingCart.java#L55). This example also shows that you can inject external services to handlers if needed.
 - Code uses [functional interfaces](https://www.theserverside.com/blog/Coffee-Talk-Java-News-Stories-and-Opinions/Get-the-most-from-Java-Function-interface-with-this-example) in many places to introduce composability and lously coupled, testable code.
 - Added [EventStoreDB aggregate store](./src/main/java/io/eventdriven/ecommerce/core/aggregates/AggregateStore.java) to load entity state and store event created by business logic.
@@ -67,7 +67,7 @@ It uses:
 ## Prerequisites
 
 1. Install git - https://git-scm.com/downloads.
-2. Install Java JDK 17 (or later) - https://www.oracle.com/java/technologies/downloads/.
+2. Install Java JDK 22 (or later) - https://www.oracle.com/java/technologies/downloads/.
 3. Install IntelliJ, Eclipse, VSCode or other preferred IDE.
 4. Install docker - https://docs.docker.com/engine/install/.
 5. Open project folder.

samples/event-sourcing-esdb-aggregates/build.gradle

@@ -6,10 +6,16 @@ plugins {
 
 java {
   toolchain {
-    languageVersion = JavaLanguageVersion.of(21)
+    languageVersion = JavaLanguageVersion.of(22)
   }
 }
 
+// workaround for https://github.com/gradle/gradle/issues/28987#issuecomment-2084711213
+// Todo: remove it once Gradle and Spring are aligned, possibly in Gralde 8.8 and Spring Boot 3.3.x
+springBoot {
+  mainClass = 'io.eventdriven.ecommerce.ECommerceApplication'
+}
+
 group = 'io.event-driven'
 version = '0.0.1-SNAPSHOT'
 

samples/event-sourcing-esdb-aggregates/gradle/wrapper/gradle-wrapper.properties

@@ -1,5 +1,7 @@
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-8.7-bin.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-8.8-rc-1-bin.zip
+networkTimeout=10000
+validateDistributionUrl=true
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists