1 /* Copyright (C) 2003 Vladimir Roubtsov. All rights reserved. 2 * 3 * This program and the accompanying materials are made available under 4 * the terms of the Common Public License v1.0 which accompanies this distribution, 5 * and is available at http://www.eclipse.org/legal/cpl-v10.html 6 * 7 * $Id: ExceptionsAttribute_info.java,v 1.1.1.1 2004/05/09 16:57:47 vlad_r Exp $ 8 */ 9 package com.vladium.jcd.cls.attribute; 10 11 import java.io.IOException; 12 13 import com.vladium.jcd.lib.UDataInputStream; 14 import com.vladium.jcd.lib.UDataOutputStream; 15 16 // ---------------------------------------------------------------------------- 17 /** 18 * The Exceptions attribute is a variable-length attribute used in the attributes 19 * table of a {@link com.vladium.jcd.cls.Method_info} structure. The Exceptions 20 * attribute indicates which checked exceptions a method may throw. There must be 21 * exactly one Exceptions attribute in each method_info structure.<P> 22 * 23 * The Exceptions attribute has the following format: 24 * <PRE> 25 * Exceptions_attribute { 26 * u2 attribute_name_index; 27 * u4 attribute_length; 28 * u2 number_of_exceptions; 29 * u2 exception_index_table[number_of_exceptions]; 30 * } 31 * </PRE> 32 * The value of the number_of_exceptions item indicates the number of entries 33 * in the exception_index_table.<P> 34 * 35 * Each nonzero value in the exception_index_table array must be a valid index 36 * into the constant_pool table. For each table item, if 37 * exception_index_table[i] != 0 , where 0 < i < number_of_exceptions, 38 * then the constant_pool entry at index exception_index_table[i] must be a 39 * {@link com.vladium.jcd.cls.constant.CONSTANT_Class_info} structure representing 40 * a class type that this method is declared to throw -- see {@link DeclaredExceptionTable}. 41 * 42 * @author (C) 2001, Vlad Roubtsov 43 */ 44 public 45 final class ExceptionsAttribute_info extends Attribute_info 46 { 47 // public: ................................................................ 48 49 // TODO: merge IDeclaredExceptionTable into this class 50 ExceptionsAttribute_info(final int attribute_name_index, final IDeclaredExceptionTable exceptions)51 public ExceptionsAttribute_info (final int attribute_name_index, 52 final IDeclaredExceptionTable exceptions) 53 { 54 super (attribute_name_index, exceptions.length ()); 55 56 m_exceptions = exceptions; 57 } 58 getDeclaredExceptions()59 public IDeclaredExceptionTable getDeclaredExceptions () 60 { 61 return m_exceptions; 62 } 63 length()64 public long length () 65 { 66 return 6 + m_exceptions.length (); 67 } 68 69 // Visitor: 70 accept(final IAttributeVisitor visitor, final Object ctx)71 public void accept (final IAttributeVisitor visitor, final Object ctx) 72 { 73 visitor.visit (this, ctx); 74 } 75 toString()76 public String toString () 77 { 78 // TODO: return more data here 79 return "ExceptionsAttribute_info: [attribute_name_index = " + m_name_index + ", attribute_length = " + m_attribute_length + ']'; 80 } 81 82 // Cloneable: 83 84 /** 85 * Performs a deep copy. 86 */ clone()87 public Object clone () 88 { 89 final ExceptionsAttribute_info _clone = (ExceptionsAttribute_info) super.clone (); 90 91 // do deep copy: 92 _clone.m_exceptions = (IDeclaredExceptionTable) m_exceptions.clone (); 93 94 return _clone; 95 } 96 97 // IClassFormatOutput: 98 writeInClassFormat(final UDataOutputStream out)99 public void writeInClassFormat (final UDataOutputStream out) throws IOException 100 { 101 super.writeInClassFormat (out); 102 103 m_exceptions.writeInClassFormat (out); 104 } 105 106 // protected: ............................................................. 107 108 // package: ............................................................... 109 110 111 ExceptionsAttribute_info(final int attribute_name_index, final long attribute_length, final UDataInputStream bytes)112 ExceptionsAttribute_info (final int attribute_name_index, final long attribute_length, 113 final UDataInputStream bytes) 114 throws IOException 115 { 116 super (attribute_name_index, attribute_length); 117 118 final int number_of_exceptions = bytes.readU2 (); 119 m_exceptions = new DeclaredExceptionTable (number_of_exceptions); 120 121 for (int i = 0; i < number_of_exceptions; i++) 122 { 123 final int exception_index = bytes.readU2 (); 124 125 m_exceptions.add (exception_index); 126 } 127 } 128 129 // private: ............................................................... 130 131 132 private IDeclaredExceptionTable m_exceptions; 133 134 } // end of class 135 // ---------------------------------------------------------------------------- 136