Valtypes 26 grammar WIP

org.eclipse.jdt.core.compiler.batch/grammar/java.g

@@ -121,6 +121,7 @@ $Terminals
 	BeginCasePattern
 	RestrictedIdentifierWhen
 	UNDERSCORE
+	RestrictedIdentifiervalue
 
 --    BodyMarker
 
@@ -230,6 +231,8 @@ Goal ::= RestrictedIdentifierpermits PermittedTypes
 -- jsr 427 --
 Goal ::= BeginCasePattern Pattern
 Goal ::= RestrictedIdentifierWhen Expression
+-- JEP 401 Value Objects and Classes Disambiguation
+Goal ::= RestrictedIdentifiervalue Modifiersopt
 /:$readableName Goal:/
 
 Literal -> IntegerLiteral
@@ -680,6 +683,7 @@ Modifier -> 'transient'
 Modifier -> 'volatile'
 Modifier -> 'strictfp'
 Modifier ::= Annotation
+Modifier -> RestrictedIdentifiervalue
 /.$putCase consumeAnnotationAsModifier(); $break ./
 /:$readableName Modifier:/
 

org.eclipse.jdt.core.compiler.batch/src/org/eclipse/jdt/internal/compiler/classfmt/ClassFileConstants.java

@@ -67,6 +67,7 @@ public interface ClassFileConstants {
 	 * Other VM flags.
 	 */
 	int AccSuper = 0x0020;
+	int AccIdentity = 0x0020;
 
 	/**
 	 * Extra flags for types and members attributes (not from the JVMS, should have been defined in ExtraCompilerModifiers).

org.eclipse.jdt.core.compiler.batch/src/org/eclipse/jdt/internal/compiler/impl/JavaFeature.java

@@ -119,6 +119,10 @@ public enum JavaFeature {
 			Messages.bind(Messages.markdown_comments),
 			CharOperation.NO_CHAR_CHAR,
 			false),
+	VALUE_CLASSES_AND_OBJECTS(ClassFileConstants.JDK26,
+			Messages.bind(Messages.primitives_in_patterns),
+			new char[][] {TypeConstants.VALUE_RESTRICTED_KEYWORD},
+			true),
     ;
 
 	final long compliance;

org.eclipse.jdt.core.compiler.batch/src/org/eclipse/jdt/internal/compiler/lookup/ExtraCompilerModifiers.java

@@ -8,6 +8,10 @@
  *
  * SPDX-License-Identifier: EPL-2.0
  *
+ * This is an implementation of an early-draft specification developed under the Java
+ * Community Process (JCP) and is made available for testing and evaluation purposes
+ * only. The code is not compatible with any specification of the JCP.
+ *
  * Contributors:
  *     IBM Corporation - initial API and implementation
  *     Stephan Herrmann <stephan@cs.tu-berlin.de> - Contributions for
@@ -36,6 +40,7 @@ public interface ExtraCompilerModifiers { // modifier constant
 	final int AccRestrictedAccess = ASTNode.Bit19;
 	final int AccFromClassFile = ASTNode.Bit20;
 	final int AccDefaultAbstract = ASTNode.Bit20;
+	final int AccValue = ASTNode.Bit20; // class that is a value class (ref ACC_IDENTITY of JVM)
 	// bit21 - use by ClassFileConstants.AccDeprecated
 	// bit22 was used for AccDeprecatedImplicitly
 	final int AccAlternateModifierProblem = ASTNode.Bit23;

org.eclipse.jdt.core.compiler.batch/src/org/eclipse/jdt/internal/compiler/lookup/TypeConstants.java

@@ -8,6 +8,10 @@
  *
  * SPDX-License-Identifier: EPL-2.0
  *
+ * This is an implementation of an early-draft specification developed under the Java
+ * Community Process (JCP) and is made available for testing and evaluation purposes
+ * only. The code is not compatible with any specification of the JCP.
+ *
  * Contributors:
  *     IBM Corporation - initial API and implementation
  *     Stephan Herrmann - Contributions for
@@ -134,6 +138,7 @@ public interface TypeConstants {
 	char[] NON_SEALED = "non-sealed".toCharArray(); //$NON-NLS-1$
 	String KEYWORD_EXTENDS = "extends"; //$NON-NLS-1$
 	String IMPLEMENTS = "implements"; //$NON-NLS-1$
+	char[] VALUE_RESTRICTED_KEYWORD = "value".toCharArray(); //$NON-NLS-1$
 
     // jsr308
 	char[] TYPE_USE_TARGET  = "TYPE_USE".toCharArray(); //$NON-NLS-1$

org.eclipse.jdt.core.compiler.batch/src/org/eclipse/jdt/internal/compiler/messages.properties

@@ -1,5 +1,5 @@
 ###############################################################################
-# Copyright (c) 2000, 2024 IBM Corporation and others.
+# Copyright (c) 2000, 2025 IBM Corporation and others.
 #
 # This program and the accompanying materials
 # are made available under the terms of the Eclipse Public License 2.0
@@ -8,6 +8,10 @@
 #
 # SPDX-License-Identifier: EPL-2.0
 #
+# This is an implementation of an early-draft specification developed under the Java
+# Community Process (JCP) and is made available for testing and evaluation purposes
+# only. The code is not compatible with any specification of the JCP.
+#
 # Contributors:
 #     IBM Corporation - initial API and implementation
 ###############################################################################
@@ -80,4 +84,4 @@ compact_source_and_instance_main_methods = Compact Source Files and Instance Mai
 flexible_constructor_bodies = Flexible Constructor Bodies
 primitives_in_patterns = Primitives In Patterns
 module_imports = Module Import Declarations
-
+value_classes_and_objects = Value Classes and Objects

org.eclipse.jdt.core.compiler.batch/src/org/eclipse/jdt/internal/compiler/parser/AbstractCommentParser.java

@@ -1,5 +1,5 @@
 /*******************************************************************************
- * Copyright (c) 2000, 2024 IBM Corporation and others.
+ * Copyright (c) 2000, 2025 IBM Corporation and others.
  *
  * This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License 2.0
@@ -8,6 +8,10 @@
  *
  * SPDX-License-Identifier: EPL-2.0
  *
+ * This is an implementation of an early-draft specification developed under the Java
+ * Community Process (JCP) and is made available for testing and evaluation purposes
+ * only. The code is not compatible with any specification of the JCP.
+ *
  * Contributors:
  *     IBM Corporation - initial API and implementation
  *******************************************************************************/
@@ -1345,6 +1349,7 @@ protected Object parseQualifiedName(boolean reset, boolean allowModule) throws I
 				case TokenNameprotected:
 				case TokenNamepublic:
 				case TokenNameRestrictedIdentifiersealed:
+				case TokenNameRestrictedIdentifiervalue:
 				case TokenNameshort:
 				case TokenNamestatic:
 				case TokenNamestrictfp: