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 */ 017package org.apache.bcel.classfile; 018 019import java.io.DataInput; 020import java.io.DataOutputStream; 021import java.io.IOException; 022 023import org.apache.bcel.Const; 024 025/** 026 * This attribute exists for local or anonymous classes and ... there can be only one. 027 * 028 * @since 6.0 029 */ 030public class EnclosingMethod extends Attribute { 031 032 // Pointer to the CONSTANT_Class_info structure representing the 033 // innermost class that encloses the declaration of the current class. 034 private int classIndex; 035 036 // If the current class is not immediately enclosed by a method or 037 // constructor, then the value of the method_index item must be zero. 038 // Otherwise, the value of the method_index item must point to a 039 // CONSTANT_NameAndType_info structure representing the name and the 040 // type of a method in the class referenced by the class we point 041 // to in the class_index. *It is the compiler responsibility* to 042 // ensure that the method identified by this index is the closest 043 // lexically enclosing method that includes the local/anonymous class. 044 private int methodIndex; 045 046 // Ctors - and code to read an attribute in. 047 EnclosingMethod(final int nameIndex, final int len, final DataInput input, final ConstantPool cpool) throws IOException { 048 this(nameIndex, len, input.readUnsignedShort(), input.readUnsignedShort(), cpool); 049 } 050 051 private EnclosingMethod(final int nameIndex, final int len, final int classIdx, final int methodIdx, final ConstantPool cpool) { 052 super(Const.ATTR_ENCLOSING_METHOD, nameIndex, len, cpool); 053 classIndex = classIdx; 054 methodIndex = methodIdx; 055 } 056 057 @Override 058 public void accept(final Visitor v) { 059 v.visitEnclosingMethod(this); 060 } 061 062 @Override 063 public Attribute copy(final ConstantPool constant_pool) { 064 return (Attribute) clone(); 065 } 066 067 @Override 068 public final void dump(final DataOutputStream file) throws IOException { 069 super.dump(file); 070 file.writeShort(classIndex); 071 file.writeShort(methodIndex); 072 } 073 074 public final ConstantClass getEnclosingClass() { 075 return super.getConstantPool().getConstant(classIndex, Const.CONSTANT_Class, ConstantClass.class); 076 } 077 078 // Accessors 079 public final int getEnclosingClassIndex() { 080 return classIndex; 081 } 082 083 public final ConstantNameAndType getEnclosingMethod() { 084 if (methodIndex == 0) { 085 return null; 086 } 087 return super.getConstantPool().getConstant(methodIndex, Const.CONSTANT_NameAndType, ConstantNameAndType.class); 088 } 089 090 public final int getEnclosingMethodIndex() { 091 return methodIndex; 092 } 093 094 public final void setEnclosingClassIndex(final int idx) { 095 classIndex = idx; 096 } 097 098 public final void setEnclosingMethodIndex(final int idx) { 099 methodIndex = idx; 100 } 101}