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.ByteArrayInputStream; 021import java.io.DataInput; 022import java.io.DataOutputStream; 023import java.io.IOException; 024 025import org.apache.bcel.Const; 026 027/** 028 * This class is derived from <em>Attribute</em> and represents a reference 029 * to a GJ attribute. 030 * 031 * @see Attribute 032 */ 033public final class Signature extends Attribute { 034 035 private int signature_index; 036 037 038 /** 039 * Initialize from another object. Note that both objects use the same 040 * references (shallow copy). Use clone() for a physical copy. 041 */ 042 public Signature(final Signature c) { 043 this(c.getNameIndex(), c.getLength(), c.getSignatureIndex(), c.getConstantPool()); 044 } 045 046 047 /** 048 * Construct object from file stream. 049 * @param name_index Index in constant pool to CONSTANT_Utf8 050 * @param length Content length in bytes 051 * @param input Input stream 052 * @param constant_pool Array of constants 053 * @throws IOException 054 */ 055 Signature(final int name_index, final int length, final DataInput input, final ConstantPool constant_pool) 056 throws IOException { 057 this(name_index, length, input.readUnsignedShort(), constant_pool); 058 } 059 060 061 /** 062 * @param name_index Index in constant pool to CONSTANT_Utf8 063 * @param length Content length in bytes 064 * @param signature_index Index in constant pool to CONSTANT_Utf8 065 * @param constant_pool Array of constants 066 */ 067 public Signature(final int name_index, final int length, final int signature_index, final ConstantPool constant_pool) { 068 super(Const.ATTR_SIGNATURE, name_index, length, constant_pool); 069 this.signature_index = signature_index; 070 } 071 072 073 /** 074 * Called by objects that are traversing the nodes of the tree implicitely 075 * defined by the contents of a Java class. I.e., the hierarchy of methods, 076 * fields, attributes, etc. spawns a tree of objects. 077 * 078 * @param v Visitor object 079 */ 080 @Override 081 public void accept( final Visitor v ) { 082 //System.err.println("Visiting non-standard Signature object"); 083 v.visitSignature(this); 084 } 085 086 087 /** 088 * Dump source file attribute to file stream in binary format. 089 * 090 * @param file Output file stream 091 * @throws IOException 092 */ 093 @Override 094 public void dump( final DataOutputStream file ) throws IOException { 095 super.dump(file); 096 file.writeShort(signature_index); 097 } 098 099 100 /** 101 * @return Index in constant pool of source file name. 102 */ 103 public int getSignatureIndex() { 104 return signature_index; 105 } 106 107 108 /** 109 * @param signature_index the index info the constant pool of this signature 110 */ 111 public void setSignatureIndex( final int signature_index ) { 112 this.signature_index = signature_index; 113 } 114 115 116 /** 117 * @return GJ signature. 118 */ 119 public String getSignature() { 120 final ConstantUtf8 c = (ConstantUtf8) super.getConstantPool().getConstant(signature_index, 121 Const.CONSTANT_Utf8); 122 return c.getBytes(); 123 } 124 125 /** 126 * Extends ByteArrayInputStream to make 'unreading' chars possible. 127 */ 128 private static final class MyByteArrayInputStream extends ByteArrayInputStream { 129 130 MyByteArrayInputStream(final String data) { 131 super(data.getBytes()); 132 } 133 134 135 String getData() { 136 return new String(buf); 137 } 138 139 140 void unread() { 141 if (pos > 0) { 142 pos--; 143 } 144 } 145 } 146 147 148 private static boolean identStart( final int ch ) { 149 return ch == 'T' || ch == 'L'; 150 } 151 152 153 private static void matchIdent( final MyByteArrayInputStream in, final StringBuilder buf ) { 154 int ch; 155 if ((ch = in.read()) == -1) { 156 throw new RuntimeException("Illegal signature: " + in.getData() 157 + " no ident, reaching EOF"); 158 } 159 //System.out.println("return from ident:" + (char)ch); 160 if (!identStart(ch)) { 161 final StringBuilder buf2 = new StringBuilder(); 162 int count = 1; 163 while (Character.isJavaIdentifierPart((char) ch)) { 164 buf2.append((char) ch); 165 count++; 166 ch = in.read(); 167 } 168 if (ch == ':') { // Ok, formal parameter 169 in.skip("Ljava/lang/Object".length()); 170 buf.append(buf2); 171 ch = in.read(); 172 in.unread(); 173 //System.out.println("so far:" + buf2 + ":next:" +(char)ch); 174 } else { 175 for (int i = 0; i < count; i++) { 176 in.unread(); 177 } 178 } 179 return; 180 } 181 final StringBuilder buf2 = new StringBuilder(); 182 ch = in.read(); 183 do { 184 buf2.append((char) ch); 185 ch = in.read(); 186 //System.out.println("within ident:"+ (char)ch); 187 } while ((ch != -1) && (Character.isJavaIdentifierPart((char) ch) || (ch == '/'))); 188 buf.append(buf2.toString().replace('/', '.')); 189 //System.out.println("regular return ident:"+ (char)ch + ":" + buf2); 190 if (ch != -1) { 191 in.unread(); 192 } 193 } 194 195 196 private static void matchGJIdent( final MyByteArrayInputStream in, final StringBuilder buf ) { 197 int ch; 198 matchIdent(in, buf); 199 ch = in.read(); 200 if ((ch == '<') || ch == '(') { // Parameterized or method 201 //System.out.println("Enter <"); 202 buf.append((char) ch); 203 matchGJIdent(in, buf); 204 while (((ch = in.read()) != '>') && (ch != ')')) { // List of parameters 205 if (ch == -1) { 206 throw new RuntimeException("Illegal signature: " + in.getData() 207 + " reaching EOF"); 208 } 209 //System.out.println("Still no >"); 210 buf.append(", "); 211 in.unread(); 212 matchGJIdent(in, buf); // Recursive call 213 } 214 //System.out.println("Exit >"); 215 buf.append((char) ch); 216 } else { 217 in.unread(); 218 } 219 ch = in.read(); 220 if (identStart(ch)) { 221 in.unread(); 222 matchGJIdent(in, buf); 223 } else if (ch == ')') { 224 in.unread(); 225 return; 226 } else if (ch != ';') { 227 throw new RuntimeException("Illegal signature: " + in.getData() + " read " + (char) ch); 228 } 229 } 230 231 232 public static String translate( final String s ) { 233 //System.out.println("Sig:" + s); 234 final StringBuilder buf = new StringBuilder(); 235 matchGJIdent(new MyByteArrayInputStream(s), buf); 236 return buf.toString(); 237 } 238 239 240 // @since 6.0 is no longer final 241 public static boolean isFormalParameterList( final String s ) { 242 return s.startsWith("<") && (s.indexOf(':') > 0); 243 } 244 245 246 // @since 6.0 is no longer final 247 public static boolean isActualParameterList( final String s ) { 248 return s.startsWith("L") && s.endsWith(">;"); 249 } 250 251 252 /** 253 * @return String representation 254 */ 255 @Override 256 public String toString() { 257 final String s = getSignature(); 258 return "Signature: " + s; 259 } 260 261 262 /** 263 * @return deep copy of this attribute 264 */ 265 @Override 266 public Attribute copy( final ConstantPool _constant_pool ) { 267 return (Attribute) clone(); 268 } 269}