Use --release 8 for builds targeting Java 8 (apache#23771)

* Use --release 8 for builds targeting Java 8 This ensures cross compilation works correctly when building on JDK 11 and targeting Java 8. * Update buildSrc/src/main/groovy/org/apache/beam/gradle/BeamModulePlugin.groovy Co-authored-by: Lukasz Cwik <lcwik@google.com> * Review feedback * Update buildSrc/src/main/groovy/org/apache/beam/gradle/BeamModulePlugin.groovy Co-authored-by: Lukasz Cwik <lcwik@google.com> * Adjust javaVersion configuration Co-authored-by: Lukasz Cwik <lcwik@google.com>
cushon · Oct 28, 2022 · feaa1a2 · feaa1a2
1 parent a62fe8f
commit feaa1a2
Show file tree

Hide file tree

Showing 2 changed files with 16 additions and 3 deletions.
diff --git a/buildSrc/src/main/groovy/org/apache/beam/gradle/BeamModulePlugin.groovy b/buildSrc/src/main/groovy/org/apache/beam/gradle/BeamModulePlugin.groovy
@@ -914,6 +914,15 @@ class BeamModulePlugin implements Plugin<Project> {
 
       project.tasks.withType(JavaCompile).configureEach {
         options.encoding = "UTF-8"
+        // Use --release 8 when targeting Java 8 and running on JDK > 8
+        //
+        // Consider migrating compilation and testing to use JDK 9+ and setting '--release=8' as
+        // the default allowing 'applyJavaNature' to override it for the few modules that need JDK 9+
+        // artifacts. See https://stackoverflow.com/a/43103038/4368200 for additional details.
+        if (JavaVersion.VERSION_1_8.compareTo(JavaVersion.toVersion(project.javaVersion)) == 0
+        && JavaVersion.VERSION_1_8.compareTo(JavaVersion.current()) < 0) {
+          options.compilerArgs += ['--release', '8']
+        }
         // As we want to add '-Xlint:-deprecation' we intentionally remove '-Xlint:deprecation' from compilerArgs here,
         // as intellij is adding this, see https://youtrack.jetbrains.com/issue/IDEA-196615
         options.compilerArgs -= [

diff --git a/sdks/java/container/agent/build.gradle b/sdks/java/container/agent/build.gradle
@@ -19,6 +19,13 @@
 plugins {
     id 'org.apache.beam.module'
 }
+
+if (project.hasProperty('java11Home')) {
+    javaVersion = "1.11"
+} else if (project.hasProperty('java17Home')) {
+    javaVersion = "1.17"
+}
+
 applyJavaNature(
     exportJavadoc: false,
     publish: false
@@ -35,17 +42,14 @@ jar {
     }
 }
 
-
 if (project.hasProperty('java11Home')) {
-    javaVersion = "1.11"
     def java11Home = project.findProperty('java11Home')
     project.tasks.withType(JavaCompile) {
         options.fork = true
         options.forkOptions.javaHome = java11Home as File
         options.compilerArgs += ['-Xlint:-path']
     }
 } else if (project.hasProperty('java17Home')) {
-    javaVersion = "1.17"
     project.tasks.withType(JavaCompile) {
         setJava17Options(options)