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 * reserved comment block

 * DO NOT REMOVE OR ALTER!

 */

/*

 * Licensed to the Apache Software Foundation (ASF) under one or more

 * contributor license agreements.  See the NOTICE file distributed with

 * this work for additional information regarding copyright ownership.

 * The ASF licenses this file to You under the Apache License, Version 2.0

 * (the "License"); you may not use this file except in compliance with

 * the License.  You may obtain a copy of the License at

 *

 *      http://www.apache.org/licenses/LICENSE-2.0

 *

 * Unless required by applicable law or agreed to in writing, software

 * distributed under the License is distributed on an "AS IS" BASIS,

 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

 * See the License for the specific language governing permissions and

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package com.sun.org.apache.bcel.internal.classfile;

import java.io.DataInput;

import java.io.DataOutputStream;

import java.io.IOException;

import com.sun.org.apache.bcel.internal.Const;

/**

 * This class is derived from <em>Attribute</em> and represents a constant

 * value, i.e., a default value for initializing a class field.

 * This class is instantiated by the <em>Attribute.readAttribute()</em> method.

 *

 * @see     Attribute

 */

public final class ConstantValue extends Attribute {

    private int constantValueIndex;

    /**

     * Initialize from another object. Note that both objects use the same

     * references (shallow copy). Use clone() for a physical copy.

     */

    public ConstantValue(final ConstantValue c) {

        this(c.getNameIndex(), c.getLength(), c.getConstantValueIndex(), c.getConstantPool());

    }

    /**

     * Construct object from input stream.

     * @param name_index Name index in constant pool

     * @param length Content length in bytes

     * @param input Input stream

     * @param constant_pool Array of constants

     * @throws IOException

     */

    ConstantValue(final int name_index, final int length, final DataInput input, final ConstantPool constant_pool)

            throws IOException {

        this(name_index, length, input.readUnsignedShort(), constant_pool);

    }

    /**

     * @param name_index Name index in constant pool

     * @param length Content length in bytes

     * @param constantValueIndex Index in constant pool

     * @param constant_pool Array of constants

     */

    public ConstantValue(final int name_index, final int length, final int constantValueIndex,

            final ConstantPool constant_pool) {

        super(Const.ATTR_CONSTANT_VALUE, name_index, length, constant_pool);

        this.constantValueIndex = constantValueIndex;

    }

    /**

     * Called by objects that are traversing the nodes of the tree implicitely

     * defined by the contents of a Java class. I.e., the hierarchy of methods,

     * fields, attributes, etc. spawns a tree of objects.

     *

     * @param v Visitor object

     */

    @Override

    public void accept( final Visitor v ) {

        v.visitConstantValue(this);

    }

    /**

     * Dump constant value attribute to file stream on binary format.

     *

     * @param file Output file stream

     * @throws IOException

     */

    @Override

    public void dump( final DataOutputStream file ) throws IOException {

        super.dump(file);

        file.writeShort(constantValueIndex);

    }

    /**

     * @return Index in constant pool of constant value.

     */

    public int getConstantValueIndex() {

        return constantValueIndex;

    }

    /**

     * @param constantValueIndex the index info the constant pool of this constant value

     */

    public void setConstantValueIndex( final int constantValueIndex ) {

        this.constantValueIndex = constantValueIndex;

    }

    /**

     * @return String representation of constant value.

     */

    @Override

    public String toString() {

        Constant c = super.getConstantPool().getConstant(constantValueIndex);

        String buf;

        int i;

        // Print constant to string depending on its type

        switch (c.getTag()) {

            case Const.CONSTANT_Long:

                buf = String.valueOf(((ConstantLong) c).getBytes());

                break;

            case Const.CONSTANT_Float:

                buf = String.valueOf(((ConstantFloat) c).getBytes());

                break;

            case Const.CONSTANT_Double:

                buf = String.valueOf(((ConstantDouble) c).getBytes());

                break;

            case Const.CONSTANT_Integer:

                buf = String.valueOf(((ConstantInteger) c).getBytes());

                break;

            case Const.CONSTANT_String:

                i = ((ConstantString) c).getStringIndex();

                c = super.getConstantPool().getConstant(i, Const.CONSTANT_Utf8);

                buf = "\"" + Utility.convertString(((ConstantUtf8) c).getBytes()) + "\"";

                break;

            default:

                throw new IllegalStateException("Type of ConstValue invalid: " + c);

        }

        return buf;

    }

    /**

     * @return deep copy of this attribute

     */

    @Override

    public Attribute copy( final ConstantPool _constant_pool ) {

        final ConstantValue c = (ConstantValue) clone();

        c.setConstantPool(_constant_pool);

        return c;

    }

}