Add assertions that a compatible JVM is installed and used for the test

Author: laeubi

org.eclipse.jdt.debug.tests/multirelease/src/p/Main.java

@@ -3,7 +3,7 @@
 public class Main {
 
 	public static void main(String[] args) {
-		System.out.println("Main: "+java.lang.Runtime.version());
+		System.out.println("Java: "+java.lang.Runtime.version().feature());
 		new X().greet();
 	}
 

org.eclipse.jdt.debug.tests/test plugin/org/eclipse/jdt/debug/testplugin/JavaProjectHelper.java

@@ -108,7 +108,7 @@ public class JavaProjectHelper {
 	public static final IPath TEST_24_SRC_DIR = new Path("java24");
 
 	/**
-	 * path to the 21 test source
+	 * path to the multirelease test source
 	 */
 	public static final IPath TEST_MR_SRC_DIR = new Path("multirelease");
 
@@ -315,7 +315,8 @@ public static void delete(IJavaProject jproject) throws CoreException {
 	/**
 	 * Adds a new source container specified by the container name to the source path of the specified project
 	 *
-	 * @param extra optional extra classpaht attributes
+	 * @param extra
+	 *            optional extra classpath attributes
 	 * @return the package fragment root of the container name
 	 */
 	public static IPackageFragmentRoot addSourceContainer(IJavaProject jproject, String containerName, IClasspathAttribute... extra) throws CoreException {

org.eclipse.jdt.debug.tests/tests/org/eclipse/jdt/debug/tests/AbstractDebugTest.java

@@ -643,7 +643,6 @@ synchronized void assertMRProject() {
 				File root = JavaTestPlugin.getDefault().getFileInPlugin(JavaProjectHelper.TEST_MR_SRC_DIR);
 				JavaProjectHelper.importFilesFromDirectory(new File(root, src17.getPath().lastSegment()), src17.getPath(), null);
 				JavaProjectHelper.importFilesFromDirectory(new File(root, src21.getPath().lastSegment()), src21.getPath(), null);
-				// TODO
 				cfgs.add(createLaunchConfiguration(jp, "p.Main"));
 				loadedMR = true;
 				waitForBuild();

org.eclipse.jdt.debug.tests/tests/org/eclipse/jdt/debug/tests/core/MultiReleaseLaunchTests.java

@@ -14,6 +14,10 @@
 package org.eclipse.jdt.debug.tests.core;
 
 import java.io.StringReader;
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.Iterator;
+import java.util.List;
 import java.util.Properties;
 
 import org.eclipse.debug.core.DebugPlugin;
@@ -23,16 +27,37 @@
 import org.eclipse.jdt.core.IJavaProject;
 import org.eclipse.jdt.debug.core.IJavaDebugTarget;
 import org.eclipse.jdt.debug.tests.ui.AbstractDebugUiTests;
+import org.eclipse.jdt.launching.IVMInstall;
+import org.eclipse.jdt.launching.IVMInstall2;
+import org.eclipse.jdt.launching.IVMInstallType;
+import org.eclipse.jdt.launching.JavaRuntime;
 import org.eclipse.jface.text.IDocument;
 import org.eclipse.ui.console.IConsole;
 import org.eclipse.ui.console.TextConsole;
 
+/**
+ * <b>IMPORTANT</b> This test requires some different JVM installs to be present (see {@link #JAVA_11}, {@link #JAVA_17}, {@link #JAVA_21})) if such
+ * JVMs can not be found, the test will fail!
+ */
 public class MultiReleaseLaunchTests extends AbstractDebugUiTests {
 
+	private static final RequiredJavaVersion JAVA_11 = new RequiredJavaVersion(11, 16);
+	private static final RequiredJavaVersion JAVA_17 = new RequiredJavaVersion(17, 20);
+	private static final RequiredJavaVersion JAVA_21 = new RequiredJavaVersion(21, Integer.MAX_VALUE);
+
 	public MultiReleaseLaunchTests(String name) {
 		super(name);
 	}
 
+	@Override
+	protected void setUp() throws Exception {
+		super.setUp();
+		List<RequiredJavaVersion> requiredJavaVersions = new ArrayList<>(List.of(JAVA_11, JAVA_17, JAVA_21));
+		removeExistingJavaVersions(requiredJavaVersions);
+		assertTrue("The following java versions are required by this test but can not be found: "
+				+ requiredJavaVersions, requiredJavaVersions.isEmpty());
+	}
+
 	@Override
 	protected IJavaProject getProjectContext() {
 		return getMultireleaseProject();
@@ -41,14 +66,17 @@ protected IJavaProject getProjectContext() {
 	public void testMultiReleaseLaunch() throws Exception {
 		ILaunchConfiguration config = getLaunchConfiguration("p.Main");
 		Properties result = launchAndReadResult(config, 11);
+		assertTrue("Was not launched with a proper Java installation " + result, JAVA_11.matches(result.getProperty("Java")));
 		assertEquals("X should be executed from Java 11 version: " + result, "11", result.get("X"));
 		assertNull("Y should not be executed from Java 11 version: " + result, result.get("Y"));
 		assertNull("Z should not be executed from Java 11 version: " + result, result.get("Z"));
 		Properties result17 = launchAndReadResult(config, 17);
+		assertTrue("Was not launched with a proper Java installation " + result17, JAVA_17.matches(result17.getProperty("Java")));
 		assertEquals("X should be executed from Java 17 version: " + result17, "17", result17.get("X"));
 		assertEquals("Y should be executed from Java 11 version: " + result17, "11", result17.get("Y"));
 		assertNull("Z should not be executed from Java 17 version: " + result17, result17.get("Z"));
 		Properties result21 = launchAndReadResult(config, 21);
+		assertTrue("Was not launched with a proper Java installation " + result21, JAVA_21.matches(result21.getProperty("Java")));
 		assertEquals("X should be executed from Java 17 version: " + result21, "17", result21.get("X"));
 		assertEquals("Y should be executed from Java 21 version: " + result21, "21", result21.get("Y"));
 		assertEquals("Z should be executed from Java 17 version: " + result21, "17", result21.get("Z"));
@@ -70,4 +98,46 @@ private Properties launchAndReadResult(ILaunchConfiguration config, int javaVers
 		return properties;
 	}
 
+	private static int getJavaVersion(IVMInstall install) {
+		if (install instanceof IVMInstall2 vm) {
+			try {
+				String javaVersion = vm.getJavaVersion().split("\\.")[0]; //$NON-NLS-1$
+				return Integer.parseInt(javaVersion);
+			} catch (RuntimeException rte) {
+				// can't know then...
+			}
+		}
+		return -1;
+	}
+
+	private static void removeExistingJavaVersions(Collection<RequiredJavaVersion> requiredJavaVersions) {
+		IVMInstallType[] installTypes = JavaRuntime.getVMInstallTypes();
+		for (IVMInstallType installType : installTypes) {
+			IVMInstall[] vmInstalls = installType.getVMInstalls();
+			for (IVMInstall install : vmInstalls) {
+				if (requiredJavaVersions.isEmpty()) {
+					return;
+				}
+				int javaVersion = getJavaVersion(install);
+				for (Iterator<RequiredJavaVersion> iterator = requiredJavaVersions.iterator(); iterator.hasNext();) {
+					if (iterator.next().matches(javaVersion)) {
+						iterator.remove();
+						break;
+					}
+				}
+			}
+		}
+	}
+
+	private static record RequiredJavaVersion(int from, int to) {
+
+		public boolean matches(int version) {
+			return (version >= from() && version <= to());
+		}
+
+		public boolean matches(String v) {
+			return matches(Integer.parseInt(v));
+		}
+	}
+
 }