001/* 002 * Licensed to the Apache Software Foundation (ASF) under one or more 003 * contributor license agreements. See the NOTICE file distributed with 004 * this work for additional information regarding copyright ownership. 005 * The ASF licenses this file to You under the Apache License, Version 2.0 006 * (the "License"); you may not use this file except in compliance with 007 * the License. You may obtain a copy of the License at 008 * 009 * http://www.apache.org/licenses/LICENSE-2.0 010 * 011 * Unless required by applicable law or agreed to in writing, software 012 * distributed under the License is distributed on an "AS IS" BASIS, 013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 014 * See the License for the specific language governing permissions and 015 * limitations under the License. 016 * 017 */ 018package org.apache.bcel.generic; 019 020import org.apache.bcel.Const; 021 022/** 023 * Returnaddress, the type JSR or JSR_W instructions push upon the stack. 024 * 025 * see vmspec2 �3.3.3 026 * @version $Id: ReturnaddressType.java 1806200 2017-08-25 16:33:06Z ggregory $ 027 */ 028public class ReturnaddressType extends Type { 029 030 public static final ReturnaddressType NO_TARGET = new ReturnaddressType(); 031 private InstructionHandle returnTarget; 032 033 034 /** 035 * A Returnaddress [that doesn't know where to return to]. 036 */ 037 private ReturnaddressType() { 038 super(Const.T_ADDRESS, "<return address>"); 039 } 040 041 042 /** 043 * Creates a ReturnaddressType object with a target. 044 */ 045 public ReturnaddressType(final InstructionHandle returnTarget) { 046 super(Const.T_ADDRESS, "<return address targeting " + returnTarget + ">"); 047 this.returnTarget = returnTarget; 048 } 049 050 051 /** @return a hash code value for the object. 052 */ 053 @Override 054 public int hashCode() { 055 if (returnTarget == null) { 056 return 0; 057 } 058 return returnTarget.hashCode(); 059 } 060 061 062 /** 063 * Returns if the two Returnaddresses refer to the same target. 064 */ 065 @Override 066 public boolean equals( final Object rat ) { 067 if (!(rat instanceof ReturnaddressType)) { 068 return false; 069 } 070 final ReturnaddressType that = (ReturnaddressType) rat; 071 if (this.returnTarget == null || that.returnTarget == null) { 072 return that.returnTarget == this.returnTarget; 073 } 074 return that.returnTarget.equals(this.returnTarget); 075 } 076 077 078 /** 079 * @return the target of this ReturnaddressType 080 */ 081 public InstructionHandle getTarget() { 082 return returnTarget; 083 } 084}