/*

 * Copyright (c) 2007, 2016, 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 com.sun.tools.classfile;

import java.io.IOException;

import java.lang.reflect.Constructor;

import java.util.HashMap;

import java.util.Map;

/**

 *  <p><b>This is NOT part of any supported API.

 *  If you write code that depends on this, you do so at your own risk.

 *  This code and its internal interfaces are subject to change or

 *  deletion without notice.</b>

 */

public abstract class Attribute {

    public static final String AnnotationDefault        = "AnnotationDefault";

    public static final String BootstrapMethods         = "BootstrapMethods";

    public static final String CharacterRangeTable      = "CharacterRangeTable";

    public static final String Code                     = "Code";

    public static final String ConstantValue            = "ConstantValue";

    public static final String CompilationID            = "CompilationID";

    public static final String Deprecated               = "Deprecated";

    public static final String EnclosingMethod          = "EnclosingMethod";

    public static final String Exceptions               = "Exceptions";

    public static final String InnerClasses             = "InnerClasses";

    public static final String LineNumberTable          = "LineNumberTable";

    public static final String LocalVariableTable       = "LocalVariableTable";

    public static final String LocalVariableTypeTable   = "LocalVariableTypeTable";

    public static final String MethodParameters         = "MethodParameters";

    public static final String Module                   = "Module";

    public static final String ModuleHashes             = "ModuleHashes";

    public static final String ModuleMainClass          = "ModuleMainClass";

    public static final String ModulePackages           = "ModulePackages";

    public static final String ModuleResolution         = "ModuleResolution";

    public static final String ModuleTarget             = "ModuleTarget";

    public static final String RuntimeVisibleAnnotations = "RuntimeVisibleAnnotations";

    public static final String RuntimeInvisibleAnnotations = "RuntimeInvisibleAnnotations";

    public static final String RuntimeVisibleParameterAnnotations = "RuntimeVisibleParameterAnnotations";

    public static final String RuntimeInvisibleParameterAnnotations = "RuntimeInvisibleParameterAnnotations";

    public static final String RuntimeVisibleTypeAnnotations = "RuntimeVisibleTypeAnnotations";

    public static final String RuntimeInvisibleTypeAnnotations = "RuntimeInvisibleTypeAnnotations";

    public static final String Signature                = "Signature";

    public static final String SourceDebugExtension     = "SourceDebugExtension";

    public static final String SourceFile               = "SourceFile";

    public static final String SourceID                 = "SourceID";

    public static final String StackMap                 = "StackMap";

    public static final String StackMapTable            = "StackMapTable";

    public static final String Synthetic                = "Synthetic";

    public static class Factory {

        public Factory() {

            // defer init of standardAttributeClasses until after options set up

        }

        public Attribute createAttribute(ClassReader cr, int name_index, byte[] data)

                throws IOException {

            if (standardAttributes == null) {

                init();

            }

            ConstantPool cp = cr.getConstantPool();

            String reasonForDefaultAttr;

            try {

                String name = cp.getUTF8Value(name_index);

                Class<? extends Attribute> attrClass = standardAttributes.get(name);

                if (attrClass != null) {

                    try {

                        Class<?>[] constrArgTypes = {ClassReader.class, int.class, int.class};

                        Constructor<? extends Attribute> constr = attrClass.getDeclaredConstructor(constrArgTypes);

                        return constr.newInstance(cr, name_index, data.length);

                    } catch (Throwable t) {

                        reasonForDefaultAttr = t.toString();

                        // fall through and use DefaultAttribute

                        // t.printStackTrace();

                    }

                } else {

                    reasonForDefaultAttr = "unknown attribute";

                }

            } catch (ConstantPoolException e) {

                reasonForDefaultAttr = e.toString();

                // fall through and use DefaultAttribute

            }

            return new DefaultAttribute(cr, name_index, data, reasonForDefaultAttr);

        }

        protected void init() {

            standardAttributes = new HashMap<>();

            standardAttributes.put(AnnotationDefault, AnnotationDefault_attribute.class);

            standardAttributes.put(BootstrapMethods,  BootstrapMethods_attribute.class);

            standardAttributes.put(CharacterRangeTable, CharacterRangeTable_attribute.class);

            standardAttributes.put(Code,              Code_attribute.class);

            standardAttributes.put(CompilationID,     CompilationID_attribute.class);

            standardAttributes.put(ConstantValue,     ConstantValue_attribute.class);

            standardAttributes.put(Deprecated,        Deprecated_attribute.class);

            standardAttributes.put(EnclosingMethod,   EnclosingMethod_attribute.class);

            standardAttributes.put(Exceptions,        Exceptions_attribute.class);

            standardAttributes.put(InnerClasses,      InnerClasses_attribute.class);

            standardAttributes.put(LineNumberTable,   LineNumberTable_attribute.class);

            standardAttributes.put(LocalVariableTable, LocalVariableTable_attribute.class);

            standardAttributes.put(LocalVariableTypeTable, LocalVariableTypeTable_attribute.class);

            standardAttributes.put(MethodParameters,  MethodParameters_attribute.class);

            standardAttributes.put(Module,            Module_attribute.class);

            standardAttributes.put(ModuleHashes,      ModuleHashes_attribute.class);

            standardAttributes.put(ModuleMainClass,   ModuleMainClass_attribute.class);

            standardAttributes.put(ModulePackages,    ModulePackages_attribute.class);

            standardAttributes.put(ModuleResolution,  ModuleResolution_attribute.class);

            standardAttributes.put(ModuleTarget,      ModuleTarget_attribute.class);

            standardAttributes.put(RuntimeInvisibleAnnotations, RuntimeInvisibleAnnotations_attribute.class);

            standardAttributes.put(RuntimeInvisibleParameterAnnotations, RuntimeInvisibleParameterAnnotations_attribute.class);

            standardAttributes.put(RuntimeVisibleAnnotations, RuntimeVisibleAnnotations_attribute.class);

            standardAttributes.put(RuntimeVisibleParameterAnnotations, RuntimeVisibleParameterAnnotations_attribute.class);

            standardAttributes.put(RuntimeVisibleTypeAnnotations, RuntimeVisibleTypeAnnotations_attribute.class);

            standardAttributes.put(RuntimeInvisibleTypeAnnotations, RuntimeInvisibleTypeAnnotations_attribute.class);

            standardAttributes.put(Signature,         Signature_attribute.class);

            standardAttributes.put(SourceDebugExtension, SourceDebugExtension_attribute.class);

            standardAttributes.put(SourceFile,        SourceFile_attribute.class);

            standardAttributes.put(SourceID,          SourceID_attribute.class);

            standardAttributes.put(StackMap,          StackMap_attribute.class);

            standardAttributes.put(StackMapTable,     StackMapTable_attribute.class);

            standardAttributes.put(Synthetic,         Synthetic_attribute.class);

        }

        private Map<String,Class<? extends Attribute>> standardAttributes;

    }

    public static Attribute read(ClassReader cr) throws IOException {

        return cr.readAttribute();

    }

    protected Attribute(int name_index, int length) {

        attribute_name_index = name_index;

        attribute_length = length;

    }

    public String getName(ConstantPool constant_pool) throws ConstantPoolException {

        return constant_pool.getUTF8Value(attribute_name_index);

    }

    public abstract <R,D> R accept(Attribute.Visitor<R,D> visitor, D data);

    public int byteLength() {

        return 6 + attribute_length;

    }

    public final int attribute_name_index;

    public final int attribute_length;

    public interface Visitor<R,P> {

        R visitBootstrapMethods(BootstrapMethods_attribute attr, P p);

        R visitDefault(DefaultAttribute attr, P p);

        R visitAnnotationDefault(AnnotationDefault_attribute attr, P p);

        R visitCharacterRangeTable(CharacterRangeTable_attribute attr, P p);

        R visitCode(Code_attribute attr, P p);

        R visitCompilationID(CompilationID_attribute attr, P p);

        R visitConstantValue(ConstantValue_attribute attr, P p);

        R visitDeprecated(Deprecated_attribute attr, P p);

        R visitEnclosingMethod(EnclosingMethod_attribute attr, P p);

        R visitExceptions(Exceptions_attribute attr, P p);

        R visitInnerClasses(InnerClasses_attribute attr, P p);

        R visitLineNumberTable(LineNumberTable_attribute attr, P p);

        R visitLocalVariableTable(LocalVariableTable_attribute attr, P p);

        R visitLocalVariableTypeTable(LocalVariableTypeTable_attribute attr, P p);

        R visitMethodParameters(MethodParameters_attribute attr, P p);

        R visitModule(Module_attribute attr, P p);

        R visitModuleHashes(ModuleHashes_attribute attr, P p);

        R visitModuleMainClass(ModuleMainClass_attribute attr, P p);

        R visitModulePackages(ModulePackages_attribute attr, P p);

        R visitModuleResolution(ModuleResolution_attribute attr, P p);

        R visitModuleTarget(ModuleTarget_attribute attr, P p);

        R visitRuntimeVisibleAnnotations(RuntimeVisibleAnnotations_attribute attr, P p);

        R visitRuntimeInvisibleAnnotations(RuntimeInvisibleAnnotations_attribute attr, P p);

        R visitRuntimeVisibleParameterAnnotations(RuntimeVisibleParameterAnnotations_attribute attr, P p);

        R visitRuntimeInvisibleParameterAnnotations(RuntimeInvisibleParameterAnnotations_attribute attr, P p);

        R visitRuntimeVisibleTypeAnnotations(RuntimeVisibleTypeAnnotations_attribute attr, P p);

        R visitRuntimeInvisibleTypeAnnotations(RuntimeInvisibleTypeAnnotations_attribute attr, P p);

        R visitSignature(Signature_attribute attr, P p);

        R visitSourceDebugExtension(SourceDebugExtension_attribute attr, P p);

        R visitSourceFile(SourceFile_attribute attr, P p);

        R visitSourceID(SourceID_attribute attr, P p);

        R visitStackMap(StackMap_attribute attr, P p);

        R visitStackMapTable(StackMapTable_attribute attr, P p);

        R visitSynthetic(Synthetic_attribute attr, P p);

    }

}