[23] DOM support for JEP 476: Module Import Declarations (Preview)

+ adaptations in other parts of DOM implementation
+ consistently use Modifier even for static at JLS23
+ enable DOM testing at JLS23

fixes eclipse-jdt#2834

org.eclipse.jdt.core.tests.model/src/org/eclipse/jdt/core/tests/dom/ASTTest.java

@@ -87,6 +87,7 @@
 import org.eclipse.jdt.core.dom.MethodRef;
 import org.eclipse.jdt.core.dom.MethodRefParameter;
 import org.eclipse.jdt.core.dom.Modifier;
+import org.eclipse.jdt.core.dom.Modifier.ModifierKeyword;
 import org.eclipse.jdt.core.dom.ModuleDeclaration;
 import org.eclipse.jdt.core.dom.Name;
 import org.eclipse.jdt.core.dom.NormalAnnotation;
@@ -151,6 +152,13 @@ public class ASTTest extends org.eclipse.jdt.core.tests.junit.extension.TestCase
 	 */
 	protected static final int AST_INTERNAL_JLS9 = AST.JLS9;
 
+	/**
+	 * Internal synonym for constant AST.JSL9
+	 * to alleviate deprecation warnings once AST.JLS9 is deprecated in future.
+	 * @deprecated
+	 */
+	protected static final int AST_INTERNAL_JLS23 = AST.JLS23;
+
 	class CheckPositionsMatcher extends ASTMatcher {
 
 		public CheckPositionsMatcher() {
@@ -862,6 +870,7 @@ public static Test suite() {
 				suite.addTest(new ASTTest(methods[i].getName(), JLS3_INTERNAL));
 				suite.addTest(new ASTTest(methods[i].getName(), AST.JLS4));
 				suite.addTest(new ASTTest(methods[i].getName(), getJLS8()));
+				suite.addTest(new ASTTest(methods[i].getName(), AST_INTERNAL_JLS23));
 			}
 		}
 		return suite;
@@ -2734,7 +2743,19 @@ public void set(ASTNode value) {
 		assertTrue(this.ast.modificationCount() > previousCount);
 		assertTrue(x.isOnDemand() == true);
 
-		if (this.ast.apiLevel() >= JLS3_INTERNAL) {
+		if (this.ast.apiLevel() >= AST_INTERNAL_JLS23) {
+			Modifier mod = this.ast.newModifier(ModifierKeyword.STATIC_KEYWORD);
+			x.modifiers().add(mod);
+			assertTrue(this.ast.modificationCount() > previousCount);
+			assertTrue(x.isStatic() == true);
+			previousCount = this.ast.modificationCount();
+			x.modifiers().clear();
+			mod = this.ast.newModifier(ModifierKeyword.MODULE_KEYWORD);
+			x.modifiers().add(mod);
+			assertTrue(this.ast.modificationCount() > previousCount);
+			assertTrue(x.modifiers().size() == 1);
+			assertEquals(((Modifier) x.modifiers().get(0)).getKeyword(), ModifierKeyword.MODULE_KEYWORD);
+		} else if (this.ast.apiLevel() >= JLS3_INTERNAL) {
 			x.setStatic(true);
 			assertTrue(this.ast.modificationCount() > previousCount);
 			assertTrue(x.isStatic() == true);
@@ -6643,7 +6664,11 @@ public void testSwitchCase() {
 		assertTrue(x.getParent() == null);
 		assertTrue(x.getExpression().getParent() == x);
 		assertTrue(x.getLeadingComment() == null);
-		assertTrue(!x.isDefault());
+		if (this.ast.apiLevel() < AST_INTERNAL_JLS23) {
+			assertTrue(!x.isDefault());
+		} else {
+			assertEquals(0, x.expressions().size());
+		}
 		assertTrue(x.getNodeType() == ASTNode.SWITCH_CASE);
 		assertTrue(x.structuralPropertiesForType() ==
 			SwitchCase.propertyDescriptors(this.ast.apiLevel()));

org.eclipse.jdt.core/dom/org/eclipse/jdt/core/dom/ASTMatcher.java

@@ -1129,7 +1129,11 @@ public boolean match(ImportDeclaration node, Object other) {
 			return false;
 		}
 		ImportDeclaration o = (ImportDeclaration) other;
-		if (node.getAST().apiLevel >= AST.JLS3_INTERNAL) {
+		if (node.getAST().apiLevel >= AST.JLS23_INTERNAL) {
+			if (!safeSubtreeListMatch(node.modifiers(), o.modifiers())) {
+				return false;
+			}
+		} else if (node.getAST().apiLevel >= AST.JLS3_INTERNAL) {
 			if (node.isStatic() != o.isStatic()) {
 				return false;
 			}

org.eclipse.jdt.core/dom/org/eclipse/jdt/core/dom/ImportDeclaration.java

@@ -17,6 +17,8 @@
 import java.util.ArrayList;
 import java.util.List;
 
+import org.eclipse.jdt.core.dom.Modifier.ModifierKeyword;
+
 /**
  * Import declaration AST node type.
  *
@@ -202,14 +204,14 @@ public List modifiers() {
 	 * @since 3.39
 	 */
 	public int getModifiers() {
-		int computedmodifierFlags = this.isStatic ? Modifier.STATIC : Modifier.NONE;
 		if (this.modifiers == null) {
 			// JLS3 behavior (for JLS2 this is constantly 0)
-			return computedmodifierFlags;
+			return this.isStatic ? Modifier.STATIC : Modifier.NONE;
 		}
 		// JLS23 behavior - convenience method
 		// performance could be improved by caching computed flags
 		// but this would require tracking changes to this.modifiers
+		int computedmodifierFlags = Modifier.NONE;
 		for (Object x : modifiers()) {
 			if (x instanceof Modifier modifier) {
 				computedmodifierFlags |= modifier.getKeyword().toFlagValue();
@@ -411,13 +413,35 @@ public boolean isStatic() {
 	/**
 	 * Sets whether this import declaration is a static import (added in JLS3 API).
 	 *
+	 * Note, that in JLS23 API this method creates a {@link Modifier} without source positions
+	 * (or removes, if {@code isStatic == false}), so it should not be invoked in situations where
+	 * valid source positions are required.
+	 *
 	 * @param isStatic <code>true</code> if this is a static import,
 	 *    and <code>false</code> if this is a regular import
 	 * @exception UnsupportedOperationException if this operation is used in
 	 * a JLS2 AST
 	 * @since 3.1
+	 *
+	 * @see #modifiers()
 	 */
+	@SuppressWarnings("unchecked")
 	public void setStatic(boolean isStatic) {
+		if (this.ast.apiLevel >= AST.JLS23_INTERNAL) {
+			List<Modifier> mods = modifiers();
+			for (Modifier mod : mods) {
+				if (mod.isStatic()) {
+					if (!isStatic)
+						this.modifiers.remove(mod);
+					return;
+				}
+			}
+			if (isStatic) {
+				Modifier newMod = this.ast.newModifier(ModifierKeyword.STATIC_KEYWORD);
+				this.modifiers.add(newMod);
+			}
+			return;
+		}
 		unsupportedIn2();
 		preValueChange(STATIC_PROPERTY);
 		this.isStatic = isStatic;

org.eclipse.jdt.core/dom/org/eclipse/jdt/internal/core/dom/NaiveASTFlattener.java

@@ -95,6 +95,13 @@ public class NaiveASTFlattener extends ASTVisitor {
 	 */
 	private static final int JLS21 = AST.JLS21;
 
+	/**
+	 * Internal synonym for {@link AST#JLS23}. Use to alleviate
+	 * deprecation warnings.
+	 * @deprecated
+	 */
+	private static final int JLS23 = AST.JLS23;
+
 	/**
 	 * The string buffer into which the serialized representation of the AST is
 	 * written.
@@ -845,7 +852,11 @@ public boolean visit(IfStatement node) {
 	public boolean visit(ImportDeclaration node) {
 		printIndent();
 		this.buffer.append("import ");//$NON-NLS-1$
-		if (node.getAST().apiLevel() >= JLS3) {
+		if (node.getAST().apiLevel() >= JLS23) {
+			if (node.modifiers().size() == 1) {
+				this.buffer.append(((Modifier) node.modifiers().get(0)).getKeyword().toString()).append(' ');
+			}
+		} else if (node.getAST().apiLevel() >= JLS3) {
 			if (node.isStatic()) {
 				this.buffer.append("static ");//$NON-NLS-1$
 			}

org.eclipse.jdt.core/dom/org/eclipse/jdt/internal/core/dom/rewrite/ASTRewriteFlattener.java

@@ -98,6 +98,9 @@ public class ASTRewriteFlattener extends ASTVisitor {
 	/** @deprecated using deprecated code */
 	private static final int JLS14_INTERNAL = AST.JLS14;
 
+	/** @deprecated using deprecated code */
+	private static final int JLS23_INTERNAL = AST.JLS23;
+
 	public static String asString(ASTNode node, RewriteEventStore store) {
 		ASTRewriteFlattener flattener= new ASTRewriteFlattener(store);
 		node.accept(flattener);
@@ -603,7 +606,12 @@ public boolean visit(IfStatement node) {
 	@Override
 	public boolean visit(ImportDeclaration node) {
 		this.result.append("import "); //$NON-NLS-1$
-		if (node.getAST().apiLevel() >= JLS3_INTERNAL) {
+		if (node.getAST().apiLevel() >= JLS23_INTERNAL) {
+			List<Modifier> modifiers = node.modifiers();
+			for (Modifier modifier : modifiers) {
+				this.result.append(modifier.getKeyword().toString()).append(' ');
+			}
+		} else if (node.getAST().apiLevel() >= JLS3_INTERNAL) {
 			if (getBooleanAttribute(node, ImportDeclaration.STATIC_PROPERTY)) {
 				this.result.append("static ");//$NON-NLS-1$
 			}