1/* 2 * reserved comment block 3 * DO NOT REMOVE OR ALTER! 4 */ 5/* 6 * Licensed to the Apache Software Foundation (ASF) under one or more 7 * contributor license agreements. See the NOTICE file distributed with 8 * this work for additional information regarding copyright ownership. 9 * The ASF licenses this file to You under the Apache License, Version 2.0 10 * (the "License"); you may not use this file except in compliance with 11 * the License. You may obtain a copy of the License at 12 * 13 * http://www.apache.org/licenses/LICENSE-2.0 14 * 15 * Unless required by applicable law or agreed to in writing, software 16 * distributed under the License is distributed on an "AS IS" BASIS, 17 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 18 * See the License for the specific language governing permissions and 19 * limitations under the License. 20 */ 21 22package com.sun.org.apache.bcel.internal.classfile; 23 24import java.io.DataInput; 25import java.io.DataOutputStream; 26import java.io.IOException; 27 28import com.sun.org.apache.bcel.internal.Const; 29 30/** 31 * This class represents the table of exceptions that are thrown by a 32 * method. This attribute may be used once per method. The name of 33 * this class is <em>ExceptionTable</em> for historical reasons; The 34 * Java Virtual Machine Specification, Second Edition defines this 35 * attribute using the name <em>Exceptions</em> (which is inconsistent 36 * with the other classes). 37 * 38 * @version $Id: ExceptionTable.java 1749603 2016-06-21 20:50:19Z ggregory $ 39 * @see Code 40 */ 41public final class ExceptionTable extends Attribute { 42 43 private int[] exception_index_table; // constant pool 44 45 46 /** 47 * Initialize from another object. Note that both objects use the same 48 * references (shallow copy). Use copy() for a physical copy. 49 */ 50 public ExceptionTable(final ExceptionTable c) { 51 this(c.getNameIndex(), c.getLength(), c.getExceptionIndexTable(), c.getConstantPool()); 52 } 53 54 55 /** 56 * @param name_index Index in constant pool 57 * @param length Content length in bytes 58 * @param exception_index_table Table of indices in constant pool 59 * @param constant_pool Array of constants 60 */ 61 public ExceptionTable(final int name_index, final int length, final int[] exception_index_table, 62 final ConstantPool constant_pool) { 63 super(Const.ATTR_EXCEPTIONS, name_index, length, constant_pool); 64 this.exception_index_table = exception_index_table != null ? exception_index_table : new int[0]; 65 } 66 67 68 /** 69 * Construct object from input stream. 70 * @param name_index Index in constant pool 71 * @param length Content length in bytes 72 * @param input Input stream 73 * @param constant_pool Array of constants 74 * @throws IOException 75 */ 76 ExceptionTable(final int name_index, final int length, final DataInput input, final ConstantPool constant_pool) throws IOException { 77 this(name_index, length, (int[]) null, constant_pool); 78 final int number_of_exceptions = input.readUnsignedShort(); 79 exception_index_table = new int[number_of_exceptions]; 80 for (int i = 0; i < number_of_exceptions; i++) { 81 exception_index_table[i] = input.readUnsignedShort(); 82 } 83 } 84 85 86 /** 87 * Called by objects that are traversing the nodes of the tree implicitely 88 * defined by the contents of a Java class. I.e., the hierarchy of methods, 89 * fields, attributes, etc. spawns a tree of objects. 90 * 91 * @param v Visitor object 92 */ 93 @Override 94 public void accept( final Visitor v ) { 95 v.visitExceptionTable(this); 96 } 97 98 99 /** 100 * Dump exceptions attribute to file stream in binary format. 101 * 102 * @param file Output file stream 103 * @throws IOException 104 */ 105 @Override 106 public final void dump( final DataOutputStream file ) throws IOException { 107 super.dump(file); 108 file.writeShort(exception_index_table.length); 109 for (final int index : exception_index_table) { 110 file.writeShort(index); 111 } 112 } 113 114 115 /** 116 * @return Array of indices into constant pool of thrown exceptions. 117 */ 118 public final int[] getExceptionIndexTable() { 119 return exception_index_table; 120 } 121 122 123 /** 124 * @return Length of exception table. 125 */ 126 public final int getNumberOfExceptions() { 127 return exception_index_table == null ? 0 : exception_index_table.length; 128 } 129 130 131 /** 132 * @return class names of thrown exceptions 133 */ 134 public final String[] getExceptionNames() { 135 final String[] names = new String[exception_index_table.length]; 136 for (int i = 0; i < exception_index_table.length; i++) { 137 names[i] = super.getConstantPool().getConstantString(exception_index_table[i], 138 Const.CONSTANT_Class).replace('/', '.'); 139 } 140 return names; 141 } 142 143 144 /** 145 * @param exception_index_table the list of exception indexes 146 * Also redefines number_of_exceptions according to table length. 147 */ 148 public final void setExceptionIndexTable( final int[] exception_index_table ) { 149 this.exception_index_table = exception_index_table != null ? exception_index_table : new int[0]; 150 } 151 152 153 /** 154 * @return String representation, i.e., a list of thrown exceptions. 155 */ 156 @Override 157 public final String toString() { 158 final StringBuilder buf = new StringBuilder(); 159 String str; 160 buf.append("Exceptions: "); 161 for (int i = 0; i < exception_index_table.length; i++) { 162 str = super.getConstantPool().getConstantString(exception_index_table[i], Const.CONSTANT_Class); 163 buf.append(Utility.compactClassName(str, false)); 164 if (i < exception_index_table.length - 1) { 165 buf.append(", "); 166 } 167 } 168 return buf.toString(); 169 } 170 171 172 /** 173 * @return deep copy of this attribute 174 */ 175 @Override 176 public Attribute copy( final ConstantPool _constant_pool ) { 177 final ExceptionTable c = (ExceptionTable) clone(); 178 if (exception_index_table != null) { 179 c.exception_index_table = new int[exception_index_table.length]; 180 System.arraycopy(exception_index_table, 0, c.exception_index_table, 0, 181 exception_index_table.length); 182 } 183 c.setConstantPool(_constant_pool); 184 return c; 185 } 186} 187