8308753: Class-File API transition to Preview

Reviewed-by: ihse, mchung, vromero

src/java.base/share/classes/java/lang/classfile/Attribute.java

@@ -0,0 +1,109 @@
+/*
+ * Copyright (c) 2022, 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 java.lang.classfile;
+
+import java.lang.classfile.attribute.AnnotationDefaultAttribute;
+import java.lang.classfile.attribute.BootstrapMethodsAttribute;
+import java.lang.classfile.attribute.CharacterRangeTableAttribute;
+import java.lang.classfile.attribute.CodeAttribute;
+import java.lang.classfile.attribute.CompilationIDAttribute;
+import java.lang.classfile.attribute.ConstantValueAttribute;
+import java.lang.classfile.attribute.DeprecatedAttribute;
+import java.lang.classfile.attribute.EnclosingMethodAttribute;
+import java.lang.classfile.attribute.ExceptionsAttribute;
+import java.lang.classfile.attribute.InnerClassesAttribute;
+import java.lang.classfile.attribute.LineNumberTableAttribute;
+import java.lang.classfile.attribute.LocalVariableTableAttribute;
+import java.lang.classfile.attribute.LocalVariableTypeTableAttribute;
+import java.lang.classfile.attribute.MethodParametersAttribute;
+import java.lang.classfile.attribute.ModuleAttribute;
+import java.lang.classfile.attribute.ModuleHashesAttribute;
+import java.lang.classfile.attribute.ModuleMainClassAttribute;
+import java.lang.classfile.attribute.ModulePackagesAttribute;
+import java.lang.classfile.attribute.ModuleResolutionAttribute;
+import java.lang.classfile.attribute.ModuleTargetAttribute;
+import java.lang.classfile.attribute.NestHostAttribute;
+import java.lang.classfile.attribute.NestMembersAttribute;
+import java.lang.classfile.attribute.PermittedSubclassesAttribute;
+import java.lang.classfile.attribute.RecordAttribute;
+import java.lang.classfile.attribute.RuntimeInvisibleAnnotationsAttribute;
+import java.lang.classfile.attribute.RuntimeInvisibleParameterAnnotationsAttribute;
+import java.lang.classfile.attribute.RuntimeInvisibleTypeAnnotationsAttribute;
+import java.lang.classfile.attribute.RuntimeVisibleAnnotationsAttribute;
+import java.lang.classfile.attribute.RuntimeVisibleParameterAnnotationsAttribute;
+import java.lang.classfile.attribute.RuntimeVisibleTypeAnnotationsAttribute;
+import java.lang.classfile.attribute.SignatureAttribute;
+import java.lang.classfile.attribute.SourceDebugExtensionAttribute;
+import java.lang.classfile.attribute.SourceFileAttribute;
+import java.lang.classfile.attribute.SourceIDAttribute;
+import java.lang.classfile.attribute.StackMapTableAttribute;
+import java.lang.classfile.attribute.SyntheticAttribute;
+import java.lang.classfile.attribute.UnknownAttribute;
+import jdk.internal.classfile.impl.BoundAttribute;
+import jdk.internal.classfile.impl.UnboundAttribute;
+import jdk.internal.javac.PreviewFeature;
+
+/**
+ * Models a classfile attribute {@jvms 4.7}.  Many, though not all, subtypes of
+ * {@linkplain Attribute} will implement {@link ClassElement}, {@link
+ * MethodElement}, {@link FieldElement}, or {@link CodeElement}; attributes that
+ * are also elements will be delivered when traversing the elements of the
+ * corresponding model type. Additionally, all attributes are accessible
+ * directly from the corresponding model type through {@link
+ * AttributedElement#findAttribute(AttributeMapper)}.
+ * @param <A> the attribute type
+ *
+ * @sealedGraph
+ * @since 22
+ */
+@PreviewFeature(feature = PreviewFeature.Feature.CLASSFILE_API)
+public sealed interface Attribute<A extends Attribute<A>>
+        extends WritableElement<A>
+        permits AnnotationDefaultAttribute, BootstrapMethodsAttribute,
+                CharacterRangeTableAttribute, CodeAttribute, CompilationIDAttribute,
+                ConstantValueAttribute, DeprecatedAttribute, EnclosingMethodAttribute,
+                ExceptionsAttribute, InnerClassesAttribute, LineNumberTableAttribute,
+                LocalVariableTableAttribute, LocalVariableTypeTableAttribute,
+                MethodParametersAttribute, ModuleAttribute, ModuleHashesAttribute,
+                ModuleMainClassAttribute, ModulePackagesAttribute, ModuleResolutionAttribute,
+                ModuleTargetAttribute, NestHostAttribute, NestMembersAttribute,
+                PermittedSubclassesAttribute,
+                RecordAttribute, RuntimeInvisibleAnnotationsAttribute,
+                RuntimeInvisibleParameterAnnotationsAttribute, RuntimeInvisibleTypeAnnotationsAttribute,
+                RuntimeVisibleAnnotationsAttribute, RuntimeVisibleParameterAnnotationsAttribute,
+                RuntimeVisibleTypeAnnotationsAttribute, SignatureAttribute,
+                SourceDebugExtensionAttribute, SourceFileAttribute, SourceIDAttribute,
+                StackMapTableAttribute, SyntheticAttribute,
+                UnknownAttribute, BoundAttribute, UnboundAttribute, CustomAttribute {
+    /**
+     * {@return the name of the attribute}
+     */
+    String attributeName();
+
+    /**
+     * {@return the {@link AttributeMapper} associated with this attribute}
+     */
+    AttributeMapper<A> attributeMapper();
+}