Fix jlink image warnings (#1143)

* Use correct value with jlink --compress option for Java 21+
* Handle class list file format change in Java 21
* Enable a couple linker integration tests
* Update Java version to 17.0.12

Author: barchetta

.github/actions/common/action.yml

@@ -85,8 +85,7 @@ runs:
       if: ${{ inputs.native-image == 'true' }}
       uses: graalvm/[email protected]
       with:
-        java-version: ${{ env.JAVA_VERSION }}
-        version: ${{ env.GRAALVM_VERSION }}
+        java-version: ${{ env.GRAALVM_VERSION || env.JAVA_VERSION }}
         components: 'native-image'
         check-for-updates: 'false'
         set-java-home: 'false'

.github/workflows/validate.yml

@@ -29,9 +29,9 @@ on:
         default: ''
 
 env:
-  JAVA_VERSION: 17
+  JAVA_VERSION: 17.0.12
   JAVA_DISTRO: oracle
-  GRAALVM_VERSION: 21.3.3.1
+  GRAALVM_VERSION: 21.0.7
   MVN_ARGS: |
     -B -fae -e
     -Dmaven.wagon.httpconnectionManager.ttlSeconds=60

linker/src/main/java/io/helidon/build/linker/ClassDataSharing.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2019, 2024 Oracle and/or its affiliates.
+ * Copyright (c) 2019, 2025 Oracle and/or its affiliates.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -26,6 +26,7 @@
 import java.util.Collection;
 import java.util.List;
 import java.util.concurrent.TimeUnit;
+import java.util.stream.Collectors;
 
 import io.helidon.build.common.OSType;
 import io.helidon.build.common.PrintStreams;
@@ -370,7 +371,19 @@ private void buildCdsArchive() throws Exception {
         }
 
         private List<String> loadClassList() throws IOException {
-            return Files.readAllLines(classListFile);
+            return Files.readAllLines(classListFile).stream()
+                    .filter(ClassDataSharing.Builder::isNotComment)
+                    .map(ClassDataSharing.Builder::head)
+                    .collect(Collectors.toList());
+        }
+
+        private static String head(String s) {
+            // Get first field in string. Assume whitespace delimiter
+            return s.split("\\s+")[0];
+        }
+
+        private static boolean isNotComment(String s) {
+            return !s.startsWith("# ");
         }
 
         private void execute(String action, String... jvmArgs) throws Exception {

linker/src/main/java/io/helidon/build/linker/Linker.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2019, 2022 Oracle and/or its affiliates.
+ * Copyright (c) 2019, 2025 Oracle and/or its affiliates.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -193,7 +193,13 @@ private void buildJlinkArguments() {
         jlinkArgs.add("--no-header-files");
         jlinkArgs.add("--no-man-pages");
         jlinkArgs.add("--compress");
-        jlinkArgs.add("2");
+
+        // The options used with --compress changed in 21
+        if (config.jdk().version().feature() >= 21) {
+            jlinkArgs.add("zip-6");
+        } else {
+            jlinkArgs.add("2");
+        }
 
         // user provided args
         jlinkArgs.addAll(config.additionalJlinkArgs());

linker/src/test/java/io/helidon/build/linker/ClassDataSharingTestIT.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2019, 2024 Oracle and/or its affiliates.
+ * Copyright (c) 2019, 2025 Oracle and/or its affiliates.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -25,10 +25,11 @@
 import io.helidon.build.common.test.utils.TestLogLevel;
 
 import org.junit.jupiter.api.BeforeAll;
-import org.junit.jupiter.api.Disabled;
 import org.junit.jupiter.api.Order;
 import org.junit.jupiter.api.Tag;
+import org.junit.jupiter.api.condition.DisabledOnOs;
 import org.junit.jupiter.api.condition.EnabledIfSystemProperty;
+import org.junit.jupiter.api.condition.OS;
 import org.junit.jupiter.params.ParameterizedTest;
 
 import static io.helidon.build.common.FileUtils.javaHome;
@@ -57,9 +58,11 @@ static void setup() {
     }
 
     @Tag("mp")
-    @Disabled("https://github.com/oracle/helidon-build-tools/issues/537")
     @ParameterizedTest
     @ConfigurationParameterSource("basedir")
+    // ClassDataSharing uses relativize with jri location and mainJar.
+    // relativize on Windows requires a shared root which is not true for this test.
+    @DisabledOnOs(OS.WINDOWS)
     void testQuickstartMp(String basedir) throws Exception {
         Path mainJar = Path.of(basedir).resolve("target/quickstart-mp.jar");
         Path archiveFile = Files.createTempFile("start", "jsa");

linker/src/test/java/io/helidon/build/linker/LinkerTestIT.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2019, 2024 Oracle and/or its affiliates.
+ * Copyright (c) 2019, 2025 Oracle and/or its affiliates.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -26,7 +26,6 @@
 import io.helidon.build.linker.util.Constants;
 import io.helidon.build.linker.util.JavaRuntime;
 
-import org.junit.jupiter.api.Disabled;
 import org.junit.jupiter.api.MethodOrderer.OrderAnnotation;
 import org.junit.jupiter.api.Order;
 import org.junit.jupiter.api.Tag;
@@ -124,7 +123,6 @@ void testQuickstartSe(String basedir) throws Exception {
     }
 
     @Tag("mp")
-    @Disabled("https://github.com/oracle/helidon-build-tools/issues/537")
     @Order(4)
     @ParameterizedTest
     @ConfigurationParameterSource("basedir")