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; 022import java.util.Arrays; 023import java.util.Iterator; 024import java.util.stream.Stream; 025 026import org.apache.bcel.Const; 027 028/** 029 * This class is derived from <em>Attribute</em> and denotes that this class is an Inner class of another. to the source 030 * file of this class. It is instantiated from the <em>Attribute.readAttribute()</em> method. 031 * 032 * @see Attribute 033 */ 034public final class InnerClasses extends Attribute implements Iterable<InnerClass> { 035 036 /** 037 * Empty array. 038 */ 039 private static final InnerClass[] EMPTY_INNER_CLASSE_ARRAY = {}; 040 041 private InnerClass[] innerClasses; 042 043 /** 044 * Initialize from another object. Note that both objects use the same references (shallow copy). Use clone() for a 045 * physical copy. 046 */ 047 public InnerClasses(final InnerClasses c) { 048 this(c.getNameIndex(), c.getLength(), c.getInnerClasses(), c.getConstantPool()); 049 } 050 051 /** 052 * Construct object from input stream. 053 * 054 * @param nameIndex Index in constant pool to CONSTANT_Utf8 055 * @param length Content length in bytes 056 * @param input Input stream 057 * @param constantPool Array of constants 058 * @throws IOException if an I/O error occurs. 059 */ 060 InnerClasses(final int nameIndex, final int length, final DataInput input, final ConstantPool constantPool) throws IOException { 061 this(nameIndex, length, (InnerClass[]) null, constantPool); 062 final int classCount = input.readUnsignedShort(); 063 innerClasses = new InnerClass[classCount]; 064 for (int i = 0; i < classCount; i++) { 065 innerClasses[i] = new InnerClass(input); 066 } 067 } 068 069 /** 070 * @param nameIndex Index in constant pool to CONSTANT_Utf8 071 * @param length Content length in bytes 072 * @param innerClasses array of inner classes attributes 073 * @param constantPool Array of constants 074 */ 075 public InnerClasses(final int nameIndex, final int length, final InnerClass[] innerClasses, final ConstantPool constantPool) { 076 super(Const.ATTR_INNER_CLASSES, nameIndex, length, constantPool); 077 this.innerClasses = innerClasses != null ? innerClasses : EMPTY_INNER_CLASSE_ARRAY; 078 } 079 080 /** 081 * Called by objects that are traversing the nodes of the tree implicitly defined by the contents of a Java class. 082 * I.e., the hierarchy of methods, fields, attributes, etc. spawns a tree of objects. 083 * 084 * @param v Visitor object 085 */ 086 @Override 087 public void accept(final Visitor v) { 088 v.visitInnerClasses(this); 089 } 090 091 /** 092 * @return deep copy of this attribute 093 */ 094 @Override 095 public Attribute copy(final ConstantPool constantPool) { 096 // TODO this could be recoded to use a lower level constructor after creating a copy of the inner classes 097 final InnerClasses c = (InnerClasses) clone(); 098 c.innerClasses = new InnerClass[innerClasses.length]; 099 Arrays.setAll(c.innerClasses, i -> innerClasses[i].copy()); 100 c.setConstantPool(constantPool); 101 return c; 102 } 103 104 /** 105 * Dump source file attribute to file stream in binary format. 106 * 107 * @param file Output file stream 108 * @throws IOException if an I/O error occurs. 109 */ 110 @Override 111 public void dump(final DataOutputStream file) throws IOException { 112 super.dump(file); 113 file.writeShort(innerClasses.length); 114 for (final InnerClass innerClass : innerClasses) { 115 innerClass.dump(file); 116 } 117 } 118 119 /** 120 * @return array of inner class "records" 121 */ 122 public InnerClass[] getInnerClasses() { 123 return innerClasses; 124 } 125 126 @Override 127 public Iterator<InnerClass> iterator() { 128 return Stream.of(innerClasses).iterator(); 129 } 130 131 /** 132 * @param innerClasses the array of inner classes 133 */ 134 public void setInnerClasses(final InnerClass[] innerClasses) { 135 this.innerClasses = innerClasses != null ? innerClasses : EMPTY_INNER_CLASSE_ARRAY; 136 } 137 138 /** 139 * @return String representation. 140 */ 141 @Override 142 public String toString() { 143 final StringBuilder buf = new StringBuilder(); 144 buf.append("InnerClasses("); 145 buf.append(innerClasses.length); 146 buf.append("):\n"); 147 for (final InnerClass innerClass : innerClasses) { 148 buf.append(innerClass.toString(super.getConstantPool())).append("\n"); 149 } 150 return buf.substring(0, buf.length() - 1); // remove the last newline 151 } 152}