Lift minimum JDK version to 21 and remove SecurityManager

* Lift minimum JDK version to 21
* Remove occurrences of SecurityManager, as getSecurityManager returns
  null since JDK 18
* Enable verbose deprecation warnings
* Replace getSubject and doAs calls,
  getSubject can no longer be activated via JRE command line as
  SecurityManager has been removed in JDK 25.
  A replacement is available since Java 21.
  doAs was deprecated and is replaced by callAll.
* Remove SecurityManager form JavaSecurityTest

Author: holgerfriedrich

.github/workflows/ci.yml

@@ -42,10 +42,10 @@ jobs:
     steps:
       - name: Checkout
         uses: actions/checkout@v6
-      - name: Set up JDK 17
+      - name: Set up JDK 21
         uses: actions/setup-java@v5
         with:
-          java-version: '17'
+          java-version: '21'
           distribution: 'temurin'
           cache: 'maven'
       - name: Build
@@ -74,10 +74,10 @@ jobs:
     steps:
       - name: Checkout
         uses: actions/checkout@v6
-      - name: Set up JDK 17
+      - name: Set up JDK 21
         uses: actions/setup-java@v5
         with:
-          java-version: '17'
+          java-version: '21'
           distribution: 'temurin'
           cache: 'maven'
       - name: Restore Maven Local Repository

archetypes/assembly/src/main/resources/archetype-resources/pom.xml

@@ -174,7 +174,7 @@
                         <!-- minimal distribution -->
                         <!--<feature>minimal</feature>-->
                     </bootFeatures>
-                    <javase>17</javase>
+                    <javase>21</javase>
                 </configuration>
             </plugin>
         </plugins>

archetypes/blueprint/src/main/resources/archetype-resources/pom.xml

@@ -63,8 +63,9 @@
                 <artifactId>maven-compiler-plugin</artifactId>
                 <version>3.15.0</version>
                 <configuration>
-                    <source>1.8</source>
-                    <target>1.8</target>
+                    <release>21</release>
+                    <source>21</source>
+                    <target>21</target>
                     <maxmem>256M</maxmem>
                 </configuration>
             </plugin>

archetypes/bundle/pom.xml

@@ -57,8 +57,9 @@
                 <groupId>org.apache.maven.plugins</groupId>
                 <artifactId>maven-compiler-plugin</artifactId>
                 <configuration>
-                    <source>1.8</source>
-                    <target>1.8</target>
+                    <release>21</release>
+                    <source>21</source>
+                    <target>21</target>
                     <maxmem>256M</maxmem>
                 </configuration>
             </plugin>

archetypes/bundle/src/main/resources/archetype-resources/pom.xml

@@ -82,8 +82,9 @@
                 <artifactId>maven-compiler-plugin</artifactId>
                 <version>3.15.0</version>
                 <configuration>
-                    <source>1.8</source>
-                    <target>1.8</target>
+                    <release>21</release>
+                    <source>21</source>
+                    <target>21</target>
                     <maxmem>256M</maxmem>
                 </configuration>
             </plugin>

archetypes/command/src/main/resources/archetype-resources/pom.xml

@@ -67,8 +67,9 @@
                 <inherited>true</inherited>
                 <version>3.15.0</version>
                 <configuration>
-                    <source>1.8</source>
-                    <target>1.8</target>
+                    <release>21</release>
+                    <source>21</source>
+                    <target>21</target>
                 </configuration>
             </plugin>
             <plugin>

assemblies/apache-karaf-integration/pom.xml

@@ -187,7 +187,7 @@
                     </bootFeatures>
                     <libraries>
                     </libraries>
-                    <javase>17</javase>
+                    <javase>21</javase>
                     <generateConsistencyReport>${project.build.directory}</generateConsistencyReport>
                     <consistencyReportProjectName>Apache Karaf Integration</consistencyReportProjectName>
                 </configuration>

assemblies/apache-karaf-minimal/pom.xml

@@ -145,7 +145,7 @@
                         !org.apache.karaf.command.acl.*,
                         *
                     </pidsToExtract>
-                    <javase>17</javase>
+                    <javase>21</javase>
                 </configuration>
             </plugin>
             <plugin>

assemblies/apache-karaf/pom.xml

@@ -178,7 +178,7 @@
                     </bootFeatures>
                     <libraries>
                     </libraries>
-                    <javase>17</javase>
+                    <javase>21</javase>
                     <generateConsistencyReport>${project.build.directory}</generateConsistencyReport>
                     <consistencyReportProjectName>Apache Karaf (full)</consistencyReportProjectName>
                 </configuration>

assemblies/features/base/src/main/filtered-resources/resources/bin/inc

@@ -282,12 +282,6 @@ setupVendorSepcifics() {
 setupDefaults() {
     DEFAULT_JAVA_OPTS="-XX:+UnlockDiagnosticVMOptions "
 
-    if [ "${VERSION}" -gt "11" ]; then
-      # TODO revisit EventAdminImpl to avoid use of Subject.getSubject(AccessController.getContext());
-      # -Djava.security.manager=allow is a workaround for SecurityController deprecation in JDK23+
-      DEFAULT_JAVA_OPTS="$DEFAULT_JAVA_OPTS -Djava.security.manager=allow "
-    fi
-
     setupVendorSepcifics
 
     DEFAULT_JAVA_OPTS="${DEFAULT_JAVA_OPTS} ${JAVA_VENDOR_OPTS}"