1 /*** 2 * ASM: a very small and fast Java bytecode manipulation framework 3 * Copyright (c) 2000-2005 INRIA, France Telecom 4 * All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 3. Neither the name of the copyright holders nor the names of its 15 * contributors may be used to endorse or promote products derived from 16 * this software without specific prior written permission. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 19 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 21 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE 22 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 23 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 24 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 25 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 26 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 27 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF 28 * THE POSSIBILITY OF SUCH DAMAGE. 29 */ 30 package org.objectweb.asm; 31 32 /** 33 * A visitor to visit a Java method. The methods of this interface must be 34 * called in the following order: [ <tt>visitAnnotationDefault</tt> ] ( 35 * <tt>visitAnnotation</tt> | <tt>visitParameterAnnotation</tt> | 36 * <tt>visitAttribute</tt> )* [ <tt>visitCode</tt> ( <tt>visit</tt><i>X</i>Insn</tt> | 37 * <tt>visitLabel</tt> | <tt>visitTryCatchBlock</tt> | <tt>visitLocalVariable</tt> | 38 * <tt>visitLineNumber</tt>)* <tt>visitMaxs</tt> ] <tt>visitEnd</tt>. In 39 * addition, the <tt>visit</tt><i>X</i>Insn</tt> and <tt>visitLabel</tt> 40 * methods must be called in the sequential order of the bytecode instructions 41 * of the visited code, and the <tt>visitLocalVariable</tt> and <tt>visitLineNumber</tt> 42 * methods must be called <i>after</i> the labels passed as arguments have been 43 * visited. 44 * 45 * @author Eric Bruneton 46 */ 47 public interface MethodVisitor { 48 49 // ------------------------------------------------------------------------- 50 // Annotations and non standard attributes 51 // ------------------------------------------------------------------------- 52 53 /** 54 * Visits the default value of this annotation interface method. 55 * 56 * @return a non null visitor to the visit the actual default value of this 57 * annotation interface method. The 'name' parameters passed to the 58 * methods of this annotation visitor are ignored. Moreover, exacly 59 * one visit method must be called on this annotation visitor, 60 * followed by visitEnd. 61 */ visitAnnotationDefault()62 AnnotationVisitor visitAnnotationDefault(); 63 64 /** 65 * Visits an annotation of this method. 66 * 67 * @param desc the class descriptor of the annotation class. 68 * @param visible <tt>true</tt> if the annotation is visible at runtime. 69 * @return a non null visitor to visit the annotation values. 70 */ visitAnnotation(String desc, boolean visible)71 AnnotationVisitor visitAnnotation(String desc, boolean visible); 72 73 /** 74 * Visits an annotation of a parameter this method. 75 * 76 * @param parameter the parameter index. 77 * @param desc the class descriptor of the annotation class. 78 * @param visible <tt>true</tt> if the annotation is visible at runtime. 79 * @return a non null visitor to visit the annotation values. 80 */ visitParameterAnnotation( int parameter, String desc, boolean visible)81 AnnotationVisitor visitParameterAnnotation( 82 int parameter, 83 String desc, 84 boolean visible); 85 86 /** 87 * Visits a non standard attribute of this method. 88 * 89 * @param attr an attribute. 90 */ visitAttribute(Attribute attr)91 void visitAttribute(Attribute attr); 92 93 /** 94 * Starts the visit of the method's code, if any (i.e. non abstract method). 95 */ visitCode()96 void visitCode(); 97 98 // ------------------------------------------------------------------------- 99 // Normal instructions 100 // ------------------------------------------------------------------------- 101 102 /** 103 * Visits a zero operand instruction. 104 * 105 * @param opcode the opcode of the instruction to be visited. This opcode is 106 * either NOP, ACONST_NULL, ICONST_M1, ICONST_0, ICONST_1, ICONST_2, 107 * ICONST_3, ICONST_4, ICONST_5, LCONST_0, LCONST_1, FCONST_0, 108 * FCONST_1, FCONST_2, DCONST_0, DCONST_1, IALOAD, LALOAD, FALOAD, 109 * DALOAD, AALOAD, BALOAD, CALOAD, SALOAD, IASTORE, LASTORE, FASTORE, 110 * DASTORE, AASTORE, BASTORE, CASTORE, SASTORE, POP, POP2, DUP, 111 * DUP_X1, DUP_X2, DUP2, DUP2_X1, DUP2_X2, SWAP, IADD, LADD, FADD, 112 * DADD, ISUB, LSUB, FSUB, DSUB, IMUL, LMUL, FMUL, DMUL, IDIV, LDIV, 113 * FDIV, DDIV, IREM, LREM, FREM, DREM, INEG, LNEG, FNEG, DNEG, ISHL, 114 * LSHL, ISHR, LSHR, IUSHR, LUSHR, IAND, LAND, IOR, LOR, IXOR, LXOR, 115 * I2L, I2F, I2D, L2I, L2F, L2D, F2I, F2L, F2D, D2I, D2L, D2F, I2B, 116 * I2C, I2S, LCMP, FCMPL, FCMPG, DCMPL, DCMPG, IRETURN, LRETURN, 117 * FRETURN, DRETURN, ARETURN, RETURN, ARRAYLENGTH, ATHROW, 118 * MONITORENTER, or MONITOREXIT. 119 */ visitInsn(int opcode)120 void visitInsn(int opcode); 121 122 /** 123 * Visits an instruction with a single int operand. 124 * 125 * @param opcode the opcode of the instruction to be visited. This opcode is 126 * either BIPUSH, SIPUSH or NEWARRAY. 127 * @param operand the operand of the instruction to be visited.<br> 128 * When opcode is BIPUSH, operand value should be between 129 * Byte.MIN_VALUE and Byte.MAX_VALUE.<br> 130 * When opcode is SIPUSH, operand value should be between 131 * Short.MIN_VALUE and Short.MAX_VALUE.<br> 132 * When opcode is NEWARRAY, operand value should be one of 133 * {@link Opcodes#T_BOOLEAN}, {@link Opcodes#T_CHAR}, 134 * {@link Opcodes#T_FLOAT}, {@link Opcodes#T_DOUBLE}, 135 * {@link Opcodes#T_BYTE}, {@link Opcodes#T_SHORT}, 136 * {@link Opcodes#T_INT} or {@link Opcodes#T_LONG}. 137 */ visitIntInsn(int opcode, int operand)138 void visitIntInsn(int opcode, int operand); 139 140 /** 141 * Visits a local variable instruction. A local variable instruction is an 142 * instruction that loads or stores the value of a local variable. 143 * 144 * @param opcode the opcode of the local variable instruction to be visited. 145 * This opcode is either ILOAD, LLOAD, FLOAD, DLOAD, ALOAD, ISTORE, 146 * LSTORE, FSTORE, DSTORE, ASTORE or RET. 147 * @param var the operand of the instruction to be visited. This operand is 148 * the index of a local variable. 149 */ visitVarInsn(int opcode, int var)150 void visitVarInsn(int opcode, int var); 151 152 /** 153 * Visits a type instruction. A type instruction is an instruction that 154 * takes a type descriptor as parameter. 155 * 156 * @param opcode the opcode of the type instruction to be visited. This 157 * opcode is either NEW, ANEWARRAY, CHECKCAST or INSTANCEOF. 158 * @param desc the operand of the instruction to be visited. This operand is 159 * must be a fully qualified class name in internal form, or the type 160 * descriptor of an array type (see {@link Type Type}). 161 */ visitTypeInsn(int opcode, String desc)162 void visitTypeInsn(int opcode, String desc); 163 164 /** 165 * Visits a field instruction. A field instruction is an instruction that 166 * loads or stores the value of a field of an object. 167 * 168 * @param opcode the opcode of the type instruction to be visited. This 169 * opcode is either GETSTATIC, PUTSTATIC, GETFIELD or PUTFIELD. 170 * @param owner the internal name of the field's owner class (see {@link 171 * Type#getInternalName() getInternalName}). 172 * @param name the field's name. 173 * @param desc the field's descriptor (see {@link Type Type}). 174 */ visitFieldInsn(int opcode, String owner, String name, String desc)175 void visitFieldInsn(int opcode, String owner, String name, String desc); 176 177 /** 178 * Visits a method instruction. A method instruction is an instruction that 179 * invokes a method. 180 * 181 * @param opcode the opcode of the type instruction to be visited. This 182 * opcode is either INVOKEVIRTUAL, INVOKESPECIAL, INVOKESTATIC or 183 * INVOKEINTERFACE. 184 * @param owner the internal name of the method's owner class (see {@link 185 * Type#getInternalName() getInternalName}). 186 * @param name the method's name. 187 * @param desc the method's descriptor (see {@link Type Type}). 188 */ visitMethodInsn(int opcode, String owner, String name, String desc)189 void visitMethodInsn(int opcode, String owner, String name, String desc); 190 191 /** 192 * Visits a jump instruction. A jump instruction is an instruction that may 193 * jump to another instruction. 194 * 195 * @param opcode the opcode of the type instruction to be visited. This 196 * opcode is either IFEQ, IFNE, IFLT, IFGE, IFGT, IFLE, IF_ICMPEQ, 197 * IF_ICMPNE, IF_ICMPLT, IF_ICMPGE, IF_ICMPGT, IF_ICMPLE, IF_ACMPEQ, 198 * IF_ACMPNE, GOTO, JSR, IFNULL or IFNONNULL. 199 * @param label the operand of the instruction to be visited. This operand 200 * is a label that designates the instruction to which the jump 201 * instruction may jump. 202 */ visitJumpInsn(int opcode, Label label)203 void visitJumpInsn(int opcode, Label label); 204 205 /** 206 * Visits a label. A label designates the instruction that will be visited 207 * just after it. 208 * 209 * @param label a {@link Label Label} object. 210 */ visitLabel(Label label)211 void visitLabel(Label label); 212 213 // ------------------------------------------------------------------------- 214 // Special instructions 215 // ------------------------------------------------------------------------- 216 217 /** 218 * Visits a LDC instruction. 219 * 220 * @param cst the constant to be loaded on the stack. This parameter must be 221 * a non null {@link Integer}, a {@link Float}, a {@link Long}, a 222 * {@link Double} a {@link String} (or a {@link Type} for 223 * <tt>.class</tt> constants, for classes whose version is 49.0 or 224 * more). 225 */ visitLdcInsn(Object cst)226 void visitLdcInsn(Object cst); 227 228 /** 229 * Visits an IINC instruction. 230 * 231 * @param var index of the local variable to be incremented. 232 * @param increment amount to increment the local variable by. 233 */ visitIincInsn(int var, int increment)234 void visitIincInsn(int var, int increment); 235 236 /** 237 * Visits a TABLESWITCH instruction. 238 * 239 * @param min the minimum key value. 240 * @param max the maximum key value. 241 * @param dflt beginning of the default handler block. 242 * @param labels beginnings of the handler blocks. <tt>labels[i]</tt> is 243 * the beginning of the handler block for the <tt>min + i</tt> key. 244 */ visitTableSwitchInsn(int min, int max, Label dflt, Label labels[])245 void visitTableSwitchInsn(int min, int max, Label dflt, Label labels[]); 246 247 /** 248 * Visits a LOOKUPSWITCH instruction. 249 * 250 * @param dflt beginning of the default handler block. 251 * @param keys the values of the keys. 252 * @param labels beginnings of the handler blocks. <tt>labels[i]</tt> is 253 * the beginning of the handler block for the <tt>keys[i]</tt> key. 254 */ visitLookupSwitchInsn(Label dflt, int keys[], Label labels[])255 void visitLookupSwitchInsn(Label dflt, int keys[], Label labels[]); 256 257 /** 258 * Visits a MULTIANEWARRAY instruction. 259 * 260 * @param desc an array type descriptor (see {@link Type Type}). 261 * @param dims number of dimensions of the array to allocate. 262 */ visitMultiANewArrayInsn(String desc, int dims)263 void visitMultiANewArrayInsn(String desc, int dims); 264 265 // ------------------------------------------------------------------------- 266 // Exceptions table entries, debug information, 267 // max stack size and max locals 268 // ------------------------------------------------------------------------- 269 270 /** 271 * Visits a try catch block. 272 * 273 * @param start beginning of the exception handler's scope (inclusive). 274 * @param end end of the exception handler's scope (exclusive). 275 * @param handler beginning of the exception handler's code. 276 * @param type internal name of the type of exceptions handled by the 277 * handler, or <tt>null</tt> to catch any exceptions (for "finally" 278 * blocks). 279 */ visitTryCatchBlock(Label start, Label end, Label handler, String type)280 void visitTryCatchBlock(Label start, Label end, Label handler, String type); 281 282 /** 283 * Visits a local variable declaration. 284 * 285 * @param name the name of a local variable. 286 * @param desc the type descriptor of this local variable. 287 * @param signature the type signature of this local variable. May be 288 * <tt>null</tt> if the local variable type does not use generic 289 * types. 290 * @param start the first instruction corresponding to the scope of this 291 * local variable (inclusive). 292 * @param end the last instruction corresponding to the scope of this local 293 * variable (exclusive). 294 * @param index the local variable's index. 295 * @throws IllegalArgumentException if one of the labels has not already 296 * been visited by this visitor (by the 297 * {@link #visitLabel visitLabel} method). 298 */ visitLocalVariable( String name, String desc, String signature, Label start, Label end, int index)299 void visitLocalVariable( 300 String name, 301 String desc, 302 String signature, 303 Label start, 304 Label end, 305 int index); 306 307 /** 308 * Visits a line number declaration. 309 * 310 * @param line a line number. This number refers to the source file from 311 * which the class was compiled. 312 * @param start the first instruction corresponding to this line number. 313 * @throws IllegalArgumentException if <tt>start</tt> has not already been 314 * visited by this visitor (by the {@link #visitLabel visitLabel} 315 * method). 316 */ visitLineNumber(int line, Label start)317 void visitLineNumber(int line, Label start); 318 319 /** 320 * Visits the maximum stack size and the maximum number of local variables 321 * of the method. 322 * 323 * @param maxStack maximum stack size of the method. 324 * @param maxLocals maximum number of local variables for the method. 325 */ visitMaxs(int maxStack, int maxLocals)326 void visitMaxs(int maxStack, int maxLocals); 327 328 /** 329 * Visits the end of the method. This method, which is the last one to be 330 * called, is used to inform the visitor that all the annotations and 331 * attributes of the method have been visited. 332 */ visitEnd()333 void visitEnd(); 334 } 335