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 * @version $Id: Signature.java 1749603 2016-06-21 20:50:19Z ggregory $ 032 * @see Attribute 033 */ 034public final class Signature extends Attribute { 035 036 private int signature_index; 037 038 039 /** 040 * Initialize from another object. Note that both objects use the same 041 * references (shallow copy). Use clone() for a physical copy. 042 */ 043 public Signature(final Signature c) { 044 this(c.getNameIndex(), c.getLength(), c.getSignatureIndex(), c.getConstantPool()); 045 } 046 047 048 /** 049 * Construct object from file stream. 050 * @param name_index Index in constant pool to CONSTANT_Utf8 051 * @param length Content length in bytes 052 * @param input Input stream 053 * @param constant_pool Array of constants 054 * @throws IOException 055 */ 056 Signature(final int name_index, final int length, final DataInput input, final ConstantPool constant_pool) 057 throws IOException { 058 this(name_index, length, input.readUnsignedShort(), constant_pool); 059 } 060 061 062 /** 063 * @param name_index Index in constant pool to CONSTANT_Utf8 064 * @param length Content length in bytes 065 * @param signature_index Index in constant pool to CONSTANT_Utf8 066 * @param constant_pool Array of constants 067 */ 068 public Signature(final int name_index, final int length, final int signature_index, final ConstantPool constant_pool) { 069 super(Const.ATTR_SIGNATURE, name_index, length, constant_pool); 070 this.signature_index = signature_index; 071 } 072 073 074 /** 075 * Called by objects that are traversing the nodes of the tree implicitely 076 * defined by the contents of a Java class. I.e., the hierarchy of methods, 077 * fields, attributes, etc. spawns a tree of objects. 078 * 079 * @param v Visitor object 080 */ 081 @Override 082 public void accept( final Visitor v ) { 083 //System.err.println("Visiting non-standard Signature object"); 084 v.visitSignature(this); 085 } 086 087 088 /** 089 * Dump source file attribute to file stream in binary format. 090 * 091 * @param file Output file stream 092 * @throws IOException 093 */ 094 @Override 095 public final void dump( final DataOutputStream file ) throws IOException { 096 super.dump(file); 097 file.writeShort(signature_index); 098 } 099 100 101 /** 102 * @return Index in constant pool of source file name. 103 */ 104 public final int getSignatureIndex() { 105 return signature_index; 106 } 107 108 109 /** 110 * @param signature_index the index info the constant pool of this signature 111 */ 112 public final void setSignatureIndex( final int signature_index ) { 113 this.signature_index = signature_index; 114 } 115 116 117 /** 118 * @return GJ signature. 119 */ 120 public final String getSignature() { 121 final ConstantUtf8 c = (ConstantUtf8) super.getConstantPool().getConstant(signature_index, 122 Const.CONSTANT_Utf8); 123 return c.getBytes(); 124 } 125 126 /** 127 * Extends ByteArrayInputStream to make 'unreading' chars possible. 128 */ 129 private static final class MyByteArrayInputStream extends ByteArrayInputStream { 130 131 MyByteArrayInputStream(final String data) { 132 super(data.getBytes()); 133 } 134 135 136 final String getData() { 137 return new String(buf); 138 } 139 140 141 final void unread() { 142 if (pos > 0) { 143 pos--; 144 } 145 } 146 } 147 148 149 private static boolean identStart( final int ch ) { 150 return ch == 'T' || ch == 'L'; 151 } 152 153 154 private static void matchIdent( final MyByteArrayInputStream in, final StringBuilder buf ) { 155 int ch; 156 if ((ch = in.read()) == -1) { 157 throw new RuntimeException("Illegal signature: " + in.getData() 158 + " no ident, reaching EOF"); 159 } 160 //System.out.println("return from ident:" + (char)ch); 161 if (!identStart(ch)) { 162 final StringBuilder buf2 = new StringBuilder(); 163 int count = 1; 164 while (Character.isJavaIdentifierPart((char) ch)) { 165 buf2.append((char) ch); 166 count++; 167 ch = in.read(); 168 } 169 if (ch == ':') { // Ok, formal parameter 170 in.skip("Ljava/lang/Object".length()); 171 buf.append(buf2); 172 ch = in.read(); 173 in.unread(); 174 //System.out.println("so far:" + buf2 + ":next:" +(char)ch); 175 } else { 176 for (int i = 0; i < count; i++) { 177 in.unread(); 178 } 179 } 180 return; 181 } 182 final StringBuilder buf2 = new StringBuilder(); 183 ch = in.read(); 184 do { 185 buf2.append((char) ch); 186 ch = in.read(); 187 //System.out.println("within ident:"+ (char)ch); 188 } while ((ch != -1) && (Character.isJavaIdentifierPart((char) ch) || (ch == '/'))); 189 buf.append(buf2.toString().replace('/', '.')); 190 //System.out.println("regular return ident:"+ (char)ch + ":" + buf2); 191 if (ch != -1) { 192 in.unread(); 193 } 194 } 195 196 197 private static void matchGJIdent( final MyByteArrayInputStream in, final StringBuilder buf ) { 198 int ch; 199 matchIdent(in, buf); 200 ch = in.read(); 201 if ((ch == '<') || ch == '(') { // Parameterized or method 202 //System.out.println("Enter <"); 203 buf.append((char) ch); 204 matchGJIdent(in, buf); 205 while (((ch = in.read()) != '>') && (ch != ')')) { // List of parameters 206 if (ch == -1) { 207 throw new RuntimeException("Illegal signature: " + in.getData() 208 + " reaching EOF"); 209 } 210 //System.out.println("Still no >"); 211 buf.append(", "); 212 in.unread(); 213 matchGJIdent(in, buf); // Recursive call 214 } 215 //System.out.println("Exit >"); 216 buf.append((char) ch); 217 } else { 218 in.unread(); 219 } 220 ch = in.read(); 221 if (identStart(ch)) { 222 in.unread(); 223 matchGJIdent(in, buf); 224 } else if (ch == ')') { 225 in.unread(); 226 return; 227 } else if (ch != ';') { 228 throw new RuntimeException("Illegal signature: " + in.getData() + " read " + (char) ch); 229 } 230 } 231 232 233 public static String translate( final String s ) { 234 //System.out.println("Sig:" + s); 235 final StringBuilder buf = new StringBuilder(); 236 matchGJIdent(new MyByteArrayInputStream(s), buf); 237 return buf.toString(); 238 } 239 240 241 // @since 6.0 is no longer final 242 public static boolean isFormalParameterList( final String s ) { 243 return s.startsWith("<") && (s.indexOf(':') > 0); 244 } 245 246 247 // @since 6.0 is no longer final 248 public static boolean isActualParameterList( final String s ) { 249 return s.startsWith("L") && s.endsWith(">;"); 250 } 251 252 253 /** 254 * @return String representation 255 */ 256 @Override 257 public final String toString() { 258 final String s = getSignature(); 259 return "Signature: " + s; 260 } 261 262 263 /** 264 * @return deep copy of this attribute 265 */ 266 @Override 267 public Attribute copy( final ConstantPool _constant_pool ) { 268 return (Attribute) clone(); 269 } 270}