JDK-8329624: Add visitors for preview language features

src/java.base/share/classes/jdk/internal/javac/PreviewFeature.java

@@ -81,6 +81,7 @@ public enum Feature {
         CLASSFILE_API,
         @JEP(number=461, title="Stream Gatherers", status="Preview")
         STREAM_GATHERERS,
+        LANGUAGE_MODEL,
         /**
          * A key for testing.
          */

src/java.compiler/share/classes/javax/annotation/processing/ProcessingEnvironment.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2005, 2022, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2005, 2024, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -123,6 +123,8 @@ public interface ProcessingEnvironment {
      * {@code false}.
      *
      * @since 13
+     * @see <a href="https://openjdk.org/jeps/12">
+     * JEP 12: Preview Features</a>
      */
     default boolean isPreviewEnabled() {
         return false;

src/java.compiler/share/classes/javax/lang/model/util/AbstractAnnotationValueVisitorPreview.java

@@ -0,0 +1,62 @@
+/*
+ * Copyright (c) 2019, 2024, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.  Oracle designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+package javax.lang.model.util;
+
+import jdk.internal.javac.PreviewFeature;
+
+import static javax.lang.model.SourceVersion.*;
+import javax.lang.model.SourceVersion;
+import javax.annotation.processing.SupportedSourceVersion;
+import javax.annotation.processing.ProcessingEnvironment;
+
+/**
+ * A skeletal visitor for annotation values with default behavior
+ * appropriate for a {@linkplain
+ * ProcessingEnvironment#isPreviewEnabled preview} source version.
+ *
+ * @param <R> the return type of this visitor's methods
+ * @param <P> the type of the additional parameter to this visitor's methods.
+ *
+ * @see <a href="AbstractAnnotationValueVisitor6.html#note_for_subclasses">
+ * <strong>Compatibility note for subclasses</strong></a>
+ * @see AbstractAnnotationValueVisitor6
+ * @see AbstractAnnotationValueVisitor7
+ * @see AbstractAnnotationValueVisitor8
+ * @see AbstractAnnotationValueVisitor9
+ * @see AbstractAnnotationValueVisitor14
+ * @since 23
+ */
+@SupportedSourceVersion(RELEASE_23)
+@PreviewFeature(feature=PreviewFeature.Feature.LANGUAGE_MODEL, reflective=true)
+public abstract class AbstractAnnotationValueVisitorPreview<R, P> extends AbstractAnnotationValueVisitor14<R, P> {
+
+    /**
+     * Constructor for concrete subclasses to call.
+     */
+    protected AbstractAnnotationValueVisitorPreview() {
+        super();
+    }
+}

src/java.compiler/share/classes/javax/lang/model/util/AbstractElementVisitorPreview.java

@@ -0,0 +1,66 @@
+/*
+ * Copyright (c) 2019, 2024, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.  Oracle designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+package javax.lang.model.util;
+
+import jdk.internal.javac.PreviewFeature;
+
+import javax.annotation.processing.SupportedSourceVersion;
+import javax.annotation.processing.ProcessingEnvironment;
+import javax.lang.model.SourceVersion;
+import javax.lang.model.element.ElementVisitor;
+import javax.lang.model.element.RecordComponentElement;
+import static javax.lang.model.SourceVersion.*;
+
+/**
+ * A skeletal visitor of program elements with default behavior
+ * appropriate for a {@linkplain
+ * ProcessingEnvironment#isPreviewEnabled preview} source version.
+ *
+ * @param <R> the return type of this visitor's methods.  Use {@link
+ *            Void} for visitors that do not need to return results.
+ * @param <P> the type of the additional parameter to this visitor's
+ *            methods.  Use {@code Void} for visitors that do not need an
+ *            additional parameter.
+ *
+ * @see <a href="AbstractElementVisitor6.html#note_for_subclasses">
+ * <strong>Compatibility note for subclasses</strong></a>
+ * @see AbstractElementVisitor6
+ * @see AbstractElementVisitor7
+ * @see AbstractElementVisitor8
+ * @see AbstractElementVisitor9
+ * @see AbstractElementVisitor14
+ * @since 23
+ */
+@SupportedSourceVersion(RELEASE_23)
+@PreviewFeature(feature=PreviewFeature.Feature.LANGUAGE_MODEL, reflective=true)
+public abstract class AbstractElementVisitorPreview<R, P> extends AbstractElementVisitor14<R, P> {
+    /**
+     * Constructor for concrete subclasses to call.
+     */
+    protected AbstractElementVisitorPreview(){
+        super();
+    }
+}

src/java.compiler/share/classes/javax/lang/model/util/AbstractTypeVisitorPreview.java

@@ -0,0 +1,64 @@
+/*
+ * Copyright (c) 2019, 2024, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.  Oracle designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+package javax.lang.model.util;
+
+import jdk.internal.javac.PreviewFeature;
+
+import javax.annotation.processing.SupportedSourceVersion;
+import javax.annotation.processing.ProcessingEnvironment;
+import javax.lang.model.SourceVersion;
+import static javax.lang.model.SourceVersion.*;
+
+/**
+ * A skeletal visitor of types with default behavior appropriate for a
+ * {@linkplain ProcessingEnvironment#isPreviewEnabled preview} source
+ * version.
+ *
+ * @param <R> the return type of this visitor's methods.  Use {@link
+ *            Void} for visitors that do not need to return results.
+ * @param <P> the type of the additional parameter to this visitor's
+ *            methods.  Use {@code Void} for visitors that do not need an
+ *            additional parameter.
+ *
+ * @see <a href="AbstractTypeVisitor6.html#note_for_subclasses">
+ * <strong>Compatibility note for subclasses</strong></a>
+ * @see AbstractTypeVisitor6
+ * @see AbstractTypeVisitor7
+ * @see AbstractTypeVisitor8
+ * @see AbstractTypeVisitor9
+ * @see AbstractTypeVisitor14
+ * @since 23
+ */
+@SupportedSourceVersion(RELEASE_23)
+@PreviewFeature(feature=PreviewFeature.Feature.LANGUAGE_MODEL, reflective=true)
+public abstract class AbstractTypeVisitorPreview<R, P> extends AbstractTypeVisitor14<R, P> {
+    /**
+     * Constructor for concrete subclasses to call.
+     */
+    protected AbstractTypeVisitorPreview() {
+        super();
+    }
+}

src/java.compiler/share/classes/javax/lang/model/util/ElementKindVisitorPreview.java

@@ -0,0 +1,89 @@
+/*
+ * Copyright (c) 2019, 2024, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.  Oracle designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+package javax.lang.model.util;
+
+import jdk.internal.javac.PreviewFeature;
+
+import javax.annotation.processing.SupportedSourceVersion;
+import javax.annotation.processing.ProcessingEnvironment;
+import javax.lang.model.element.*;
+import javax.lang.model.SourceVersion;
+import static javax.lang.model.SourceVersion.*;
+
+/**
+ * A visitor of program elements based on their {@linkplain
+ * ElementKind kind} with default behavior appropriate for a
+ * {@linkplain ProcessingEnvironment#isPreviewEnabled preview} source
+ * version.
+ *
+ * For {@linkplain
+ * Element elements} <code><i>Xyz</i></code> that may have more than one
+ * kind, the <code>visit<i>Xyz</i></code> methods in this class delegate
+ * to the <code>visit<i>Xyz</i>As<i>Kind</i></code> method corresponding to the
+ * first argument's kind.  The <code>visit<i>Xyz</i>As<i>Kind</i></code> methods
+ * call {@link #defaultAction defaultAction}, passing their arguments
+ * to {@code defaultAction}'s corresponding parameters.
+ *
+ * @apiNote
+ * Methods in this class may be overridden subject to their general
+ * contract.
+ *
+ * @param <R> the return type of this visitor's methods.  Use {@link
+ *            Void} for visitors that do not need to return results.
+ * @param <P> the type of the additional parameter to this visitor's
+ *            methods.  Use {@code Void} for visitors that do not need an
+ *            additional parameter.
+ *
+ * @see <a href="ElementKindVisitor6.html#note_for_subclasses">
+ * <strong>Compatibility note for subclasses</strong></a>
+ * @see ElementKindVisitor6
+ * @see ElementKindVisitor7
+ * @see ElementKindVisitor8
+ * @see ElementKindVisitor9
+ * @see ElementKindVisitor14
+ * @since 23
+ */
+@SupportedSourceVersion(RELEASE_23)
+@PreviewFeature(feature=PreviewFeature.Feature.LANGUAGE_MODEL, reflective=true)
+public class ElementKindVisitorPreview<R, P> extends ElementKindVisitor14<R, P> {
+    /**
+     * Constructor for concrete subclasses; uses {@code null} for the
+     * default value.
+     */
+    protected ElementKindVisitorPreview() {
+        super(null);
+    }
+
+    /**
+     * Constructor for concrete subclasses; uses the argument for the
+     * default value.
+     *
+     * @param defaultValue the value to assign to {@link #DEFAULT_VALUE}
+     */
+    protected ElementKindVisitorPreview(R defaultValue) {
+        super(defaultValue);
+    }
+}