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.classfile; 019 020import java.io.DataInput; 021import java.io.DataOutputStream; 022import java.io.IOException; 023 024import org.apache.bcel.Const; 025 026/** 027 * This class is derived from <em>Attribute</em> and represents the list of packages that are exported or opened by the Module attribute. 028 * There may be at most one ModulePackages attribute in a ClassFile structure. 029 * 030 * @see Attribute 031 */ 032public final class ModulePackages extends Attribute { 033 034 private int[] package_index_table; 035 036 037 /** 038 * Initialize from another object. Note that both objects use the same 039 * references (shallow copy). Use copy() for a physical copy. 040 */ 041 public ModulePackages(final ModulePackages c) { 042 this(c.getNameIndex(), c.getLength(), c.getPackageIndexTable(), c.getConstantPool()); 043 } 044 045 046 /** 047 * @param name_index Index in constant pool 048 * @param length Content length in bytes 049 * @param package_index_table Table of indices in constant pool 050 * @param constant_pool Array of constants 051 */ 052 public ModulePackages(final int name_index, final int length, final int[] package_index_table, 053 final ConstantPool constant_pool) { 054 super(Const.ATTR_MODULE_PACKAGES, name_index, length, constant_pool); 055 this.package_index_table = package_index_table != null ? package_index_table : new int[0]; 056 } 057 058 059 /** 060 * Construct object from input stream. 061 * @param name_index Index in constant pool 062 * @param length Content length in bytes 063 * @param input Input stream 064 * @param constant_pool Array of constants 065 * @throws IOException 066 */ 067 ModulePackages(final int name_index, final int length, final DataInput input, final ConstantPool constant_pool) throws IOException { 068 this(name_index, length, (int[]) null, constant_pool); 069 final int number_of_packages = input.readUnsignedShort(); 070 package_index_table = new int[number_of_packages]; 071 for (int i = 0; i < number_of_packages; i++) { 072 package_index_table[i] = input.readUnsignedShort(); 073 } 074 } 075 076 077 /** 078 * Called by objects that are traversing the nodes of the tree implicitely 079 * defined by the contents of a Java class. I.e., the hierarchy of methods, 080 * fields, attributes, etc. spawns a tree of objects. 081 * 082 * @param v Visitor object 083 */ 084 @Override 085 public void accept( final Visitor v ) { 086 v.visitModulePackages(this); 087 } 088 089 090 /** 091 * Dump ModulePackages attribute to file stream in binary format. 092 * 093 * @param file Output file stream 094 * @throws IOException 095 */ 096 @Override 097 public void dump( final DataOutputStream file ) throws IOException { 098 super.dump(file); 099 file.writeShort(package_index_table.length); 100 for (final int index : package_index_table) { 101 file.writeShort(index); 102 } 103 } 104 105 106 /** 107 * @return array of indices into constant pool of package names. 108 */ 109 public int[] getPackageIndexTable() { 110 return package_index_table; 111 } 112 113 114 /** 115 * @return Length of package table. 116 */ 117 public int getNumberOfPackages() { 118 return package_index_table == null ? 0 : package_index_table.length; 119 } 120 121 122 /** 123 * @return string array of package names 124 */ 125 public String[] getPackageNames() { 126 final String[] names = new String[package_index_table.length]; 127 for (int i = 0; i < package_index_table.length; i++) { 128 names[i] = super.getConstantPool().getConstantString(package_index_table[i], 129 Const.CONSTANT_Package).replace('/', '.'); 130 } 131 return names; 132 } 133 134 135 /** 136 * @param package_index_table the list of package indexes 137 * Also redefines number_of_packages according to table length. 138 */ 139 public void setPackageIndexTable( final int[] package_index_table ) { 140 this.package_index_table = package_index_table != null ? package_index_table : new int[0]; 141 } 142 143 144 /** 145 * @return String representation, i.e., a list of packages. 146 */ 147 @Override 148 public String toString() { 149 final StringBuilder buf = new StringBuilder(); 150 buf.append("ModulePackages("); 151 buf.append(package_index_table.length); 152 buf.append("):\n"); 153 for (final int index : package_index_table) { 154 final String package_name = super.getConstantPool().getConstantString(index, Const.CONSTANT_Package); 155 buf.append(" ").append(Utility.compactClassName(package_name, false)).append("\n"); 156 } 157 return buf.substring(0, buf.length()-1); // remove the last newline 158 } 159 160 161 /** 162 * @return deep copy of this attribute 163 */ 164 @Override 165 public Attribute copy( final ConstantPool _constant_pool ) { 166 final ModulePackages c = (ModulePackages) clone(); 167 if (package_index_table != null) { 168 c.package_index_table = new int[package_index_table.length]; 169 System.arraycopy(package_index_table, 0, c.package_index_table, 0, 170 package_index_table.length); 171 } 172 c.setConstantPool(_constant_pool); 173 return c; 174 } 175}