Move to Java 21

Author: purejava

.github/workflows/build_and_release_github.yml

@@ -15,7 +15,7 @@ jobs:
       - uses: actions/setup-java@v5
         with:
           distribution: 'temurin'
-          java-version: '20'
+          java-version: '21'
 
       - name: Setup Gradle
         uses: gradle/actions/setup-gradle@v4

.github/workflows/build_develop.yml

@@ -14,7 +14,7 @@ jobs:
       - uses: actions/setup-java@v5
         with:
           distribution: 'temurin'
-          java-version: '20'
+          java-version: '21'
 
       - name: Setup Gradle
         uses: gradle/actions/setup-gradle@v4

.github/workflows/codeql-analysis.yml

@@ -47,12 +47,12 @@ jobs:
       # See: https://github.com/actions/virtual-environments/issues/1187#issuecomment-686735760
       run: sudo ethtool -K eth0 tx off rx off
 
-    # Install and setup JDK 20
-    - name: Setup JDK 20
+    # Install and setup JDK 21
+    - name: Setup JDK 21
       uses: actions/setup-java@v5
       with:
         distribution: temurin
-        java-version: 20
+        java-version: 21
 
     # Initializes the CodeQL tools for scanning.
     - name: Initialize CodeQL

.idea/misc.xml

@@ -43,7 +43,7 @@ val gitVersion: groovy.lang.Closure<String> by extra
 version = gitVersion() // version set by the plugin, based on the Git tag
 
 java {
-    sourceCompatibility = JavaVersion.VERSION_20
+    sourceCompatibility = JavaVersion.VERSION_21
     withSourcesJar()
     withJavadocJar()
 }