RET.java
- /*
- * 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
- * limitations under the License.
- */
- package org.apache.bcel.generic;
- import java.io.DataOutputStream;
- import java.io.IOException;
- import org.apache.bcel.util.ByteSequence;
- /**
- * RET - Return from subroutine
- *
- * <PRE>
- * Stack: ... -> ...
- * </PRE>
- */
- public class RET extends Instruction implements IndexedInstruction, TypedInstruction {
- private boolean wide;
- private int index; // index to local variable containg the return address
- /**
- * Empty constructor needed for Instruction.readInstruction. Not to be used otherwise.
- */
- RET() {
- }
- public RET(final int index) {
- super(org.apache.bcel.Const.RET, (short) 2);
- setIndex(index); // May set wide as side effect
- }
- /**
- * 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
- */
- @Override
- public void accept(final Visitor v) {
- v.visitRET(this);
- }
- /**
- * Dump instruction as byte code to stream out.
- *
- * @param out Output stream
- */
- @Override
- public void dump(final DataOutputStream out) throws IOException {
- if (wide) {
- out.writeByte(org.apache.bcel.Const.WIDE);
- }
- out.writeByte(super.getOpcode());
- if (wide) {
- out.writeShort(index);
- } else {
- out.writeByte(index);
- }
- }
- /**
- * @return index of local variable containg the return address
- */
- @Override
- public final int getIndex() {
- return index;
- }
- /**
- * @return return address type
- */
- @Override
- public Type getType(final ConstantPoolGen cp) {
- return ReturnaddressType.NO_TARGET;
- }
- /**
- * Read needed data (e.g. index) from file.
- */
- @Override
- protected void initFromFile(final ByteSequence bytes, final boolean wide) throws IOException {
- this.wide = wide;
- if (wide) {
- index = bytes.readUnsignedShort();
- super.setLength(4);
- } else {
- index = bytes.readUnsignedByte();
- super.setLength(2);
- }
- }
- /**
- * Sets index of local variable containg the return address
- */
- @Override
- public final void setIndex(final int n) {
- if (n < 0) {
- throw new ClassGenException("Negative index value: " + n);
- }
- index = n;
- setWide();
- }
- private void setWide() {
- wide = index > org.apache.bcel.Const.MAX_BYTE;
- if (wide) {
- super.setLength(4); // Including the wide byte
- } else {
- super.setLength(2);
- }
- }
- /**
- * @return mnemonic for instruction
- */
- @Override
- public String toString(final boolean verbose) {
- return super.toString(verbose) + " " + index;
- }
- }