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 * 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
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 * distributed under the License is distributed on an "AS IS" BASIS,
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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 Also:
Version:$Id$
@LastModified: Jun 2019
/** * 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 $Id$ * @LastModified: Jun 2019 */
public abstract class CPInstruction extends Instruction implements TypedInstruction, IndexedInstruction { private int index; // index to constant pool
Empty constructor needed for Instruction.readInstruction. Not to be used otherwise.
/** * Empty constructor needed for Instruction.readInstruction. * Not to be used otherwise. */
CPInstruction() { }
Params:
  • index – to constant pool
/** * @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.
Params:
  • out – Output stream
/** * 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>">"
Params:
  • verbose – long/short format switch
Returns:mnemonic for instruction
/** * Long output format: * * &lt;name of opcode&gt; "["&lt;opcode number&gt;"]" * "("&lt;length of instruction&gt;")" "&lt;"&lt; constant pool index&gt;"&gt;" * * @param verbose long/short format switch * @return mnemonic for instruction */
@Override public String toString( final boolean verbose ) { return super.toString(verbose) + " " + index; }
Returns:mnemonic for instruction with symbolic references resolved
/** * @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.
Params:
  • bytes – input stream
  • wide – wide prefix?
/** * 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); }
Returns:index in constant pool referred by this instruction.
/** * @return index in constant pool referred by this instruction. */
@Override public final int getIndex() { return index; }
Set the index to constant pool.
Params:
  • index – in constant pool.
/** * 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; }
Returns:type related with this instruction.
/** @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); } }