/*
* Copyright 2000-2004 The Apache Software Foundation
*
* Licensed 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
* limitations under the License.
*
*/
package org.apache.bcel5_2_0.generic;
import java.io.DataOutputStream;
import java.io.IOException;
import org.apache.bcel5_2_0.util.ByteSequence;
/**
* IINC - Increment local variable by constant
*
* @version $Id: IINC.java 386056 2006-03-15 11:31:56Z tcurdt $
* @author <A HREF="mailto:m.dahm@gmx.de">M. Dahm</A>
*/
public class IINC extends LocalVariableInstruction {
private boolean wide;
private int c;
/**
* Empty constructor needed for the Class.newInstance() statement in
* Instruction.readInstruction(). Not to be used otherwise.
*/
IINC() {
}
/**
* @param n index of local variable
* @param c increment factor
*/
public IINC(int n, int c) {
super(); // Default behaviour of LocalVariableInstruction causes error
this.opcode = org.apache.bcel5_2_0.Constants.IINC;
this.length = (short) 3;
setIndex(n); // May set wide as side effect
setIncrement(c);
}
/**
* Dump instruction as byte code to stream out.
* @param out Output stream
*/
public void dump( DataOutputStream out ) throws IOException {
if (wide) {
out.writeByte(org.apache.bcel5_2_0.Constants.WIDE);
}
out.writeByte(opcode);
if (wide) {
out.writeShort(n);
out.writeShort(c);
} else {
out.writeByte(n);
out.writeByte(c);
}
}
private final void setWide() {
wide = (n > org.apache.bcel5_2_0.Constants.MAX_BYTE) || (Math.abs(c) > Byte.MAX_VALUE);
if (wide) {
length = 6; // wide byte included
} else {
length = 3;
}
}
/**
* Read needed data (e.g. index) from file.
*/
protected void initFromFile( ByteSequence bytes, boolean wide ) throws IOException {
this.wide = wide;
if (wide) {
length = 6;
n = bytes.readUnsignedShort();
c = bytes.readShort();
} else {
length = 3;
n = bytes.readUnsignedByte();
c = bytes.readByte();
}
}
/**
* @return mnemonic for instruction
*/
public String toString( boolean verbose ) {
return super.toString(verbose) + " " + c;
}
/**
* Set index of local variable.
*/
public final void setIndex( int n ) {
if (n < 0) {
throw new ClassGenException("Negative index value: " + n);
}
this.n = n;
setWide();
}
/**
* @return increment factor
*/
public final int getIncrement() {
return c;
}
/**
* Set increment factor.
*/
public final void setIncrement( int c ) {
this.c = c;
setWide();
}
/** @return int type
*/
public Type getType( ConstantPoolGen cp ) {
return Type.INT;
}
/**
* Call corresponding visitor method(s). The order is:
* Call visitor methods of implemented interfaces first, then
* call methods according to the class hierarchy in descending order,
* i.e., the most specific visitXXX() call comes last.
*
* @param v Visitor object
*/
public void accept( Visitor v ) {
v.visitLocalVariableInstruction(this);
v.visitIINC(this);
}
}