Initial preparation for Java 21

.github/workflows/maven.yml

@@ -15,25 +15,32 @@ jobs:
     strategy:
       matrix: # 'macos-14' is arm64
         os: ['ubuntu-22.04', 'macos-14', 'windows-2022']
+        java: [ 17 ]
+        include:
+        - os: ubuntu-22.04
+          java: 21
       fail-fast: false
     runs-on: ${{ matrix.os }}
 
     steps:
       - name: 'Check out repository'
         uses: actions/checkout@v4
 
-      - name: 'Set up Java'
+      - name: 'Set up Java ${{ matrix.java }}'
         uses: actions/setup-java@v4
         with:
-          java-version: 17
+          java-version: ${{ matrix.java }}
           distribution: 'temurin'
 
+      - name: Copy toolchains.xml
+        run: cat ~/.m2/toolchains.xml | tee toolchains.xml
+
       - name: 'Cache Maven packages'
         uses: actions/cache@v4
         with:
           path: ~/.m2
-          key: ${{ runner.os }}-m2-${{ hashFiles('**/pom.xml', '**/*.target') }}
-          restore-keys: ${{ runner.os }}-m2
+          key: ${{ runner.os }}-m2-${{ matrix.java }}-${{ hashFiles('**/pom.xml', '**/*.target') }}
+          restore-keys: ${{ runner.os }}-m2-${{ matrix.java }}
 
       - name: Set Maven Home environment variable
         run: echo "MAVEN_WRAPPER_HOME=$(./mvnw --version | grep "Maven home:" | cut -c 13-)" >> "$GITHUB_ENV"
@@ -46,7 +53,7 @@ jobs:
       - name: Build and test
         uses: coactions/setup-xvfb@v1.0.1
         with: 
-          run: ./mvnw clean verify "-Dmaven.home=${{ env.MAVEN_WRAPPER_HOME }}" -PuseJenkinsSnapshots -f org.eclipse.xtext.full.releng
+          run: ./mvnw --toolchains toolchains.xml clean verify "-Dmaven.home=${{ env.MAVEN_WRAPPER_HOME }}" -PuseJenkinsSnapshots -f org.eclipse.xtext.full.releng
 
       - name: Archive Test Results
         uses: actions/upload-artifact@v4
@@ -75,6 +82,9 @@ jobs:
           java-version: 17
           distribution: 'temurin'
 
+      - name: Copy toolchains.xml
+        run: cat ~/.m2/toolchains.xml | tee toolchains.xml
+
       - name: 'Cache Maven packages'
         uses: actions/cache@v4
         with:
@@ -86,7 +96,7 @@ jobs:
         run: echo "MAVEN_WRAPPER_HOME=$(./mvnw --version | grep "Maven home:" | cut -c 13-)" >> "$GITHUB_ENV"
 
       - name: Build Maven artifacts
-        run: ./mvnw clean verify "-Dmaven.home=${{ env.MAVEN_WRAPPER_HOME }}" -PuseJenkinsSnapshots -f org.eclipse.xtext.maven.releng
+        run: ./mvnw --toolchains toolchains.xml clean verify "-Dmaven.home=${{ env.MAVEN_WRAPPER_HOME }}" -PuseJenkinsSnapshots -f org.eclipse.xtext.maven.releng
 
       - name: Archive Test Results
         uses: actions/upload-artifact@v4

Jenkinsfile

@@ -58,6 +58,7 @@ pipeline {
         MAVEN_OPTS = "-Xmx1500m"
         JAVA_HOME_11_X64 = tool(type:'jdk', name:'temurin-jdk11-latest')
         JAVA_HOME_17_X64 = tool(type:'jdk', name:'temurin-jdk17-latest')
+        JAVA_HOME_21_X64 = tool(type:'jdk', name:'temurin-jdk21-latest')
       }
       steps {
         xvnc(useXauthority: true) {

org.eclipse.xtend.core.tests/src/org/eclipse/xtend/core/tests/compiler/CompilerBug427637Test.xtend

@@ -1014,7 +1014,7 @@ class CompilerBug427637Test extends AbstractXtendCompilerTest {
 										result += new WhitespaceData(leaf.offset, leaf.length, increaseIndentationChange, decreaseIndentationChange,
 											if (trace) new RuntimeException(), if (leaf.offset == 0) "" else if(leafs.containsComment) null else " ")
 									else
-										if(equalIndentationChange && leafs.leafs.last != leaf)
+										if(equalIndentationChange && leafs.leafs.lastOrNull != leaf)
 											result += new NewLineData(leaf.offset, leaf.length, increaseIndentationChange, decreaseIndentationChange, if (trace) new RuntimeException(), newLines)
 										else
 											result += new NewLineData(leaf.offset, leaf.length, if(equalIndentationChange) 0  else increaseIndentationChange, if(equalIndentationChange) 0 else decreaseIndentationChange, if (trace) new RuntimeException(), newLines)
@@ -1023,7 +1023,7 @@ class CompilerBug427637Test extends AbstractXtendCompilerTest {
 									var newLines = 1
 									if (leaf.leadingComment?.endsWithNewLine)
 										newLines = newLines - 1
-									if(equalIndentationChange && leafs.leafs.last != leaf)
+									if(equalIndentationChange && leafs.leafs.lastOrNull != leaf)
 										result += new NewLineData(leaf.offset, leaf.length, increaseIndentationChange, decreaseIndentationChange, if (trace) new RuntimeException(), newLines)
 									else
 										result += new NewLineData(leaf.offset, leaf.length, 0, 0, if (trace) new RuntimeException(), newLines)
@@ -1472,7 +1472,7 @@ class CompilerBug427637Test extends AbstractXtendCompilerTest {
 			                WhitespaceData _whitespaceData_1 = new WhitespaceData(_offset_2, _length_1, increaseIndentationChange, decreaseIndentationChange, _xifexpression_3, _xifexpression_4);
 			                result.add(_whitespaceData_1);
 			              } else {
-			                if ((equalIndentationChange && (!Objects.equals(IterableExtensions.<LeafInfo>last(leafs.getLeafs()), leaf)))) {
+			                if ((equalIndentationChange && (!Objects.equals(IterableExtensions.<LeafInfo>lastOrNull(leafs.getLeafs()), leaf)))) {
 			                  int _offset_4 = ((WhitespaceInfo)leaf).getOffset();
 			                  int _length_2 = ((WhitespaceInfo)leaf).getLength();
 			                  RuntimeException _xifexpression_6 = null;
@@ -1515,7 +1515,7 @@ class CompilerBug427637Test extends AbstractXtendCompilerTest {
 			              if (_endsWithNewLine_2) {
 			                newLines_1 = (newLines_1 - 1);
 			              }
-			              if ((equalIndentationChange && (!Objects.equals(IterableExtensions.<LeafInfo>last(leafs.getLeafs()), leaf)))) {
+			              if ((equalIndentationChange && (!Objects.equals(IterableExtensions.<LeafInfo>lastOrNull(leafs.getLeafs()), leaf)))) {
 			                int _offset_6 = ((WhitespaceInfo)leaf).getOffset();
 			                int _length_4 = ((WhitespaceInfo)leaf).getLength();
 			                RuntimeException _xifexpression_10 = null;
@@ -1672,5 +1672,5 @@ class CompilerBug427637Test extends AbstractXtendCompilerTest {
 			  }
 			}
 		''')
-	}	
+	}
 }

org.eclipse.xtend.core.tests/src/org/eclipse/xtend/core/tests/java8/compiler/CompilerBug427637Test.xtend

@@ -968,7 +968,7 @@ class CompilerBug427637Test extends org.eclipse.xtend.core.tests.compiler.Compil
 										result += new WhitespaceData(leaf.offset, leaf.length, increaseIndentationChange, decreaseIndentationChange,
 											if (trace) new RuntimeException(), if (leaf.offset == 0) "" else if(leafs.containsComment) null else " ")
 									else
-										if(equalIndentationChange && leafs.leafs.last != leaf)
+										if(equalIndentationChange && leafs.leafs.lastOrNull != leaf)
 											result += new NewLineData(leaf.offset, leaf.length, increaseIndentationChange, decreaseIndentationChange, if (trace) new RuntimeException(), newLines)
 										else
 											result += new NewLineData(leaf.offset, leaf.length, if(equalIndentationChange) 0  else increaseIndentationChange, if(equalIndentationChange) 0 else decreaseIndentationChange, if (trace) new RuntimeException(), newLines)
@@ -977,7 +977,7 @@ class CompilerBug427637Test extends org.eclipse.xtend.core.tests.compiler.Compil
 									var newLines = 1
 									if (leaf.leadingComment?.endsWithNewLine)
 										newLines = newLines - 1
-									if(equalIndentationChange && leafs.leafs.last != leaf)
+									if(equalIndentationChange && leafs.leafs.lastOrNull != leaf)
 										result += new NewLineData(leaf.offset, leaf.length, increaseIndentationChange, decreaseIndentationChange, if (trace) new RuntimeException(), newLines)
 									else
 										result += new NewLineData(leaf.offset, leaf.length, 0, 0, if (trace) new RuntimeException(), newLines)
@@ -1417,7 +1417,7 @@ class CompilerBug427637Test extends org.eclipse.xtend.core.tests.compiler.Compil
 			                WhitespaceData _whitespaceData_1 = new WhitespaceData(_offset_2, _length_1, increaseIndentationChange, decreaseIndentationChange, _xifexpression_3, _xifexpression_4);
 			                result.add(_whitespaceData_1);
 			              } else {
-			                if ((equalIndentationChange && (!Objects.equals(IterableExtensions.<LeafInfo>last(leafs.getLeafs()), leaf)))) {
+			                if ((equalIndentationChange && (!Objects.equals(IterableExtensions.<LeafInfo>lastOrNull(leafs.getLeafs()), leaf)))) {
 			                  int _offset_4 = ((WhitespaceInfo)leaf).getOffset();
 			                  int _length_2 = ((WhitespaceInfo)leaf).getLength();
 			                  RuntimeException _xifexpression_6 = null;
@@ -1460,7 +1460,7 @@ class CompilerBug427637Test extends org.eclipse.xtend.core.tests.compiler.Compil
 			              if (_endsWithNewLine_2) {
 			                newLines_1 = (newLines_1 - 1);
 			              }
-			              if ((equalIndentationChange && (!Objects.equals(IterableExtensions.<LeafInfo>last(leafs.getLeafs()), leaf)))) {
+			              if ((equalIndentationChange && (!Objects.equals(IterableExtensions.<LeafInfo>lastOrNull(leafs.getLeafs()), leaf)))) {
 			                int _offset_6 = ((WhitespaceInfo)leaf).getOffset();
 			                int _length_4 = ((WhitespaceInfo)leaf).getLength();
 			                RuntimeException _xifexpression_10 = null;
@@ -1613,5 +1613,5 @@ class CompilerBug427637Test extends org.eclipse.xtend.core.tests.compiler.Compil
 			  }
 			}
 		''')
-	}		
+	}
 }

org.eclipse.xtend.core.tests/src/org/eclipse/xtend/core/tests/macro/declaration/DeclarationsTest.xtend

@@ -34,7 +34,7 @@ class DeclarationsTest extends AbstractXtendTestCase {
 
 	@Test def testAnnotation() {
 		validFile('''
-			@SuppressWarnings("unused")
+			@testdata.stubs.StubbedSuppressWarnings("unused")
 			class MyClass {
 				@com.google.inject.Inject(optional=true) MyClass foo
 			}
@@ -44,10 +44,12 @@ class DeclarationsTest extends AbstractXtendTestCase {
 			assertEquals('MyClass', clazz.qualifiedName)
 			val suppressWarning = clazz.annotations.head
 			val supressWarningsDeclaration = suppressWarning.annotationTypeDeclaration
-			assertEquals('java.lang.SuppressWarnings', supressWarningsDeclaration.qualifiedName)
+			assertEquals('testdata.stubs.StubbedSuppressWarnings', supressWarningsDeclaration.qualifiedName)
 			assertEquals('unused', suppressWarning.getStringArrayValue('value').get(0))
 
-			assertEquals(2, supressWarningsDeclaration.annotations.size)
+			val annotations = supressWarningsDeclaration.annotations
+			assertEquals(annotations.map[it.annotationTypeDeclaration].toString,
+				2, annotations.size)
 
 			val valueProperty = supressWarningsDeclaration.declaredMembers.filter(typeof(AnnotationTypeElementDeclaration)).head
 			assertEquals("String[]", valueProperty.type.toString)

org.eclipse.xtend.core.tests/src/org/eclipse/xtend/core/tests/resource/ImportedNamesTest.xtend

@@ -9,12 +9,11 @@
 package org.eclipse.xtend.core.tests.resource
 
 import com.google.inject.Inject
+import java.util.Comparator
 import org.eclipse.xtend.core.tests.AbstractXtendTestCase
 import org.eclipse.xtext.resource.IResourceDescription
-import org.junit.Test
 import org.junit.Assert
-import java.util.Arrays
-import java.util.Comparator
+import org.junit.Test
 
 class ImportedNamesTest extends AbstractXtendTestCase {
 	@Inject
@@ -138,37 +137,37 @@ class ImportedNamesTest extends AbstractXtendTestCase {
 			import java.util.AbstractMap.*;
 
 			class C {
-				val list = new java.util.ArrayList<Map.Entry>
+				val list = new testdata.stubs.StubbedArrayList<Map.Entry>
 				val entry = new SimpleEntry(null, null)
 				val int i = 0
 			}
 		''', true)
 		val description = resourceDescriptionManager.getResourceDescription(file.eResource)
 		val importedNames = description.importedNames
-		Assert.assertEquals(Arrays.asList(
-				"java.io.serializable",
-				"java.lang.cloneable",
-				"java.lang.iterable",
-				"java.lang.java$util$arraylist",
-				"java.lang.object",
-				"java.util.abstractcollection",
-				"java.util.abstractlist",
-				"java.util.abstractmap",
-				"java.util.abstractmap.java$util$arraylist",
-				"java.util.abstractmap.simpleentry",
-				"java.util.abstractmap$java$util$arraylist",
-				"java.util.abstractmap$simpleentry",
-				"java.util.arraylist",
-				"java.util.collection",
-				"java.util.list",
-				"java.util.map",
-				"java.util.map$entry",
-				"java.util.randomaccess",
-				"java.util$abstractmap$java$util$arraylist",
-				"java$util$abstractmap$java$util$arraylist",
-				"my.pack.c",
-				"my.pack.java$util$arraylist",
-				"org.eclipse.xtext.xbase.lib.java$util$arraylist").join("\n"),
+		Assert.assertEquals('''
+				java.io.serializable
+				java.lang.cloneable
+				java.lang.iterable
+				java.lang.object
+				java.lang.testdata$stubs$stubbedarraylist
+				java.util.abstractcollection
+				java.util.abstractmap
+				java.util.abstractmap.simpleentry
+				java.util.abstractmap.testdata$stubs$stubbedarraylist
+				java.util.abstractmap$simpleentry
+				java.util.abstractmap$testdata$stubs$stubbedarraylist
+				java.util.collection
+				java.util.map
+				java.util.map$entry
+				java.util.randomaccess
+				java.util$abstractmap$testdata$stubs$stubbedarraylist
+				java$util$abstractmap$testdata$stubs$stubbedarraylist
+				my.pack.c
+				my.pack.testdata$stubs$stubbedarraylist
+				org.eclipse.xtext.xbase.lib.testdata$stubs$stubbedarraylist
+				testdata.stubs.stubbedabstractlist
+				testdata.stubs.stubbedarraylist
+				testdata.stubs.stubbedlist'''.toString.replace("\r", ""),
 				importedNames.toList.sortWith(Comparator.naturalOrder).join("\n"));
 	}
 }

org.eclipse.xtend.core.tests/src/org/eclipse/xtend/core/tests/typesystem/SuperTypeTests.xtend

@@ -12,12 +12,12 @@ import com.google.inject.Inject
 import java.io.Serializable
 import java.util.Collection
 import java.util.Collections
-import java.util.List
 import org.eclipse.xtend.core.jvmmodel.IXtendJvmAssociations
+import org.eclipse.xtext.util.JavaRuntimeVersion
 import org.eclipse.xtext.xbase.typesystem.references.LightweightTypeReference
 import org.junit.Ignore
 import org.junit.Test
-import org.eclipse.xtext.util.JavaRuntimeVersion
+import testdata.stubs.StubbedList
 
 /**
  * @author Sebastian Zarnekow
@@ -167,12 +167,12 @@ class SuperTypesTest extends AbstractSuperTypesTest {
 
 	@Test
 	override void testRawList() {
-		typeof(List).assertSuperTypes("Collection")
+		typeof(StubbedList).assertSuperTypes("Collection")
 	}
 
 	@Test
 	override void testStringList() {
-		"java.util.List<String>".assertSuperTypes("Collection<String>")
+		"testdata.stubs.StubbedList<String>".assertSuperTypes("Collection<String>")
 	}
 
 	@Test
@@ -277,23 +277,23 @@ class AllSuperTypesTest extends AbstractSuperTypesTest {
 
 	@Test
 	override void testRawList() {
-		typeof(List).assertSuperTypes("Collection", "Iterable", "Object")
+		typeof(StubbedList).assertSuperTypes("Collection", "Iterable", "Object")
 	}
 
 	@Test
 	override void testStringList() {
-		"java.util.List<String>".assertSuperTypes("Collection<String>", "Iterable<String>", "Object")
+		"testdata.stubs.StubbedList<String>".assertSuperTypes("Collection<String>", "Iterable<String>", "Object")
 	}
 
 	@Test
 	override void testStringArrayArrayList() {
-		"java.util.ArrayList<? extends String[]>".assertSuperTypes(
-			"AbstractList<? extends String[]>", 
+		"testdata.stubs.StubbedArrayList<? extends String[]>".assertSuperTypes(
+			"StubbedAbstractList<? extends String[]>", 
 			"RandomAccess",
 			"Cloneable",
 			"Serializable",
 			"AbstractCollection<? extends String[]>", 
-			"List<? extends String[]>",
+			"StubbedList<? extends String[]>",
 			"Collection<? extends String[]>",
 			"Iterable<? extends String[]>",
 			"Object")

org.eclipse.xtend.core.tests/testdata/testdata/stubs/StubbedAbstractList.java

@@ -0,0 +1,21 @@
+/*******************************************************************************
+ * Copyright (c) 2024 Lorenzo Bettini and others.
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Public License 2.0 which is available at
+ * http://www.eclipse.org/legal/epl-2.0.
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ *******************************************************************************/
+package testdata.stubs;
+
+import java.util.AbstractCollection;
+
+/**
+ * A stub type to use instead of relying on Java API like AbstractList, whose methods and supertypes might change in newer versions (see,
+ * e.g., https://docs.oracle.com/en/java/javase/21/docs/api/java.base/java/util/SequencedCollection.html).
+ * 
+ * @author Lorenzo Bettini - Initial contribution and API
+ */
+public abstract class StubbedAbstractList<E> extends AbstractCollection<E> implements StubbedList<E> {
+
+}

org.eclipse.xtend.core.tests/testdata/testdata/stubs/StubbedArrayList.java

@@ -0,0 +1,34 @@
+/*******************************************************************************
+ * Copyright (c) 2024 Lorenzo Bettini and others.
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Public License 2.0 which is available at
+ * http://www.eclipse.org/legal/epl-2.0.
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ *******************************************************************************/
+package testdata.stubs;
+
+import java.util.Iterator;
+import java.util.RandomAccess;
+
+/**
+ * A stub type to use instead of relying on Java API like AbstractList, whose methods and supertypes might change in newer versions (see,
+ * e.g., https://docs.oracle.com/en/java/javase/21/docs/api/java.base/java/util/SequencedCollection.html).
+ * 
+ * @author Lorenzo Bettini - Initial contribution and API
+ */
+@SuppressWarnings("serial")
+public class StubbedArrayList<E> extends StubbedAbstractList<E>
+		implements RandomAccess, Cloneable, java.io.Serializable {
+
+	@Override
+	public Iterator<E> iterator() {
+		return null;
+	}
+
+	@Override
+	public int size() {
+		return 0;
+	}
+
+}