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 * reserved comment block

 * DO NOT REMOVE OR ALTER!

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/*

 * 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,

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 * See the License for the specific language governing permissions and

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

import java.io.DataOutputStream;

import java.io.IOException;

import com.sun.org.apache.bcel.internal.classfile.Constant;

import com.sun.org.apache.bcel.internal.classfile.ConstantClass;

import com.sun.org.apache.bcel.internal.classfile.ConstantPool;

import com.sun.org.apache.bcel.internal.util.ByteSequence;

/**

 * Abstract super class for instructions that use an index into the constant

 * pool such as LDC, INVOKEVIRTUAL, etc.

 *

 * @see ConstantPoolGen

 * @see LDC

 * @see INVOKEVIRTUAL

 *

 * @version $Id: CPInstruction.java 1749603 2016-06-21 20:50:19Z ggregory $

 */

public abstract class CPInstruction extends Instruction implements TypedInstruction,

        IndexedInstruction {

    private int index; // index to constant pool

    /**

     * Empty constructor needed for the Class.newInstance() statement in

     * Instruction.readInstruction(). Not to be used otherwise.

     */

    CPInstruction() {

    }

    /**

     * @param index to constant pool

     */

    protected CPInstruction(final short opcode, final int index) {

        super(opcode, (short) 3);

        setIndex(index);

    }

    /**

     * Dump instruction as byte code to stream out.

     *

     * @param out Output stream

     */

    @Override

    public void dump(final DataOutputStream out) throws IOException {

        out.writeByte(super.getOpcode());

        out.writeShort(index);

    }

    /**

     * Long output format:

     *

     * <name of opcode> "["<opcode number>"]" "("<length of

     * instruction>")" "<"< constant pool index>">"

     *

     * @param verbose long/short format switch

     * @return mnemonic for instruction

     */

    @Override

    public String toString(final boolean verbose) {

        return super.toString(verbose) + " " + index;

    }

    /**

     * @return mnemonic for instruction with symbolic references resolved

     */

    @Override

    public String toString(final ConstantPool cp) {

        final Constant c = cp.getConstant(index);

        String str = cp.constantToString(c);

        if (c instanceof ConstantClass) {

            str = str.replace('.', '/');

        }

        return com.sun.org.apache.bcel.internal.Const.getOpcodeName(super.getOpcode()) + " " + str;

    }

    /**

     * Read needed data (i.e., index) from file.

     *

     * @param bytes input stream

     * @param wide wide prefix?

     */

    @Override

    protected void initFromFile(final ByteSequence bytes, final boolean wide) throws IOException {

        setIndex(bytes.readUnsignedShort());

        super.setLength(3);

    }

    /**

     * @return index in constant pool referred by this instruction.

     */

    @Override

    public final int getIndex() {

        return index;

    }

    /**

     * Set the index to constant pool.

     *

     * @param index in constant pool.

     */

    @Override

    public void setIndex(final int index) { // TODO could be package-protected?

        if (index < 0) {

            throw new ClassGenException("Negative index value: " + index);

        }

        this.index = index;

    }

    /**

     * @return type related with this instruction.

     */

    @Override

    public Type getType(final ConstantPoolGen cpg) {

        final ConstantPool cp = cpg.getConstantPool();

        String name = cp.getConstantString(index, com.sun.org.apache.bcel.internal.Const.CONSTANT_Class);

        if (!name.startsWith("[")) {

            name = "L" + name + ";";

        }

        return Type.getType(name);

    }

}