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1   /*
2    * Copyright (c) 2005, 2009, Oracle and/or its affiliates. All rights reserved.
3    * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4    *
5    * This code is free software; you can redistribute it and/or modify it
6    * under the terms of the GNU General Public License version 2 only, as
7    * published by the Free Software Foundation.  Oracle designates this
8    * particular file as subject to the "Classpath" exception as provided
9    * by Oracle in the LICENSE file that accompanied this code.
10   *
11   * This code is distributed in the hope that it will be useful, but WITHOUT
12   * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13   * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
14   * version 2 for more details (a copy is included in the LICENSE file that
15   * accompanied this code).
16   *
17   * You should have received a copy of the GNU General Public License version
18   * 2 along with this work; if not, write to the Free Software Foundation,
19   * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20   *
21   * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22   * or visit www.oracle.com if you need additional information or have any
23   * questions.
24   */
25  
26  /*
27   * This file is available under and governed by the GNU General Public
28   * License version 2 only, as published by the Free Software Foundation.
29   * However, the following notice accompanied the original version of this
30   * file:
31   *
32   * ASM: a very small and fast Java bytecode manipulation framework
33   * Copyright (c) 2000-2007 INRIA, France Telecom
34   * All rights reserved.
35   *
36   * Redistribution and use in source and binary forms, with or without
37   * modification, are permitted provided that the following conditions
38   * are met:
39   * 1. Redistributions of source code must retain the above copyright
40   *    notice, this list of conditions and the following disclaimer.
41   * 2. Redistributions in binary form must reproduce the above copyright
42   *    notice, this list of conditions and the following disclaimer in the
43   *    documentation and/or other materials provided with the distribution.
44   * 3. Neither the name of the copyright holders nor the names of its
45   *    contributors may be used to endorse or promote products derived from
46   *    this software without specific prior written permission.
47   *
48   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
49   * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
50   * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
51   * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
52   * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
53   * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
54   * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
55   * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
56   * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
57   * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
58   * THE POSSIBILITY OF SUCH DAMAGE.
59   */
60  package com.sun.xml.internal.ws.org.objectweb.asm;
61  
62  /**
63   * A visitor to visit a Java method. The methods of this interface must be
64   * called in the following order: [ <tt>visitAnnotationDefault</tt> ] (
65   * <tt>visitAnnotation</tt> | <tt>visitParameterAnnotation</tt> |
66   * <tt>visitAttribute</tt> )* [ <tt>visitCode</tt> ( <tt>visitFrame</tt> |
67   * <tt>visit</tt><i>X</i>Insn</tt> | <tt>visitLabel</tt> | <tt>visitTryCatchBlock</tt> |
68   * <tt>visitLocalVariable</tt> | <tt>visitLineNumber</tt>)* <tt>visitMaxs</tt> ]
69   * <tt>visitEnd</tt>. In addition, the <tt>visit</tt><i>X</i>Insn</tt>
70   * and <tt>visitLabel</tt> methods must be called in the sequential order of
71   * the bytecode instructions of the visited code, <tt>visitTryCatchBlock</tt>
72   * must be called <i>before</i> the labels passed as arguments have been
73   * visited, and the <tt>visitLocalVariable</tt> and <tt>visitLineNumber</tt>
74   * methods must be called <i>after</i> the labels passed as arguments have been
75   * visited.
76   *
77   * @author Eric Bruneton
78   */
79  public interface MethodVisitor {
80  
81      // -------------------------------------------------------------------------
82      // Annotations and non standard attributes
83      // -------------------------------------------------------------------------
84  
85      /**
86       * Visits the default value of this annotation interface method.
87       *
88       * @return a visitor to the visit the actual default value of this
89       *         annotation interface method, or <tt>null</tt> if this visitor
90       *         is not interested in visiting this default value. The 'name'
91       *         parameters passed to the methods of this annotation visitor are
92       *         ignored. Moreover, exacly one visit method must be called on this
93       *         annotation visitor, followed by visitEnd.
94       */
95      AnnotationVisitor visitAnnotationDefault();
96  
97      /**
98       * Visits an annotation of this method.
99       *
100      * @param desc the class descriptor of the annotation class.
101      * @param visible <tt>true</tt> if the annotation is visible at runtime.
102      * @return a visitor to visit the annotation values, or <tt>null</tt> if
103      *         this visitor is not interested in visiting this annotation.
104      */
105     AnnotationVisitor visitAnnotation(String desc, boolean visible);
106 
107     /**
108      * Visits an annotation of a parameter this method.
109      *
110      * @param parameter the parameter index.
111      * @param desc the class descriptor of the annotation class.
112      * @param visible <tt>true</tt> if the annotation is visible at runtime.
113      * @return a visitor to visit the annotation values, or <tt>null</tt> if
114      *         this visitor is not interested in visiting this annotation.
115      */
116     AnnotationVisitor visitParameterAnnotation(
117         int parameter,
118         String desc,
119         boolean visible);
120 
121     /**
122      * Visits a non standard attribute of this method.
123      *
124      * @param attr an attribute.
125      */
126     void visitAttribute(Attribute attr);
127 
128     /**
129      * Starts the visit of the method's code, if any (i.e. non abstract method).
130      */
131     void visitCode();
132 
133     /**
134      * Visits the current state of the local variables and operand stack
135      * elements. This method must(*) be called <i>just before</i> any
136      * instruction <b>i</b> that follows an unconditionnal branch instruction
137      * such as GOTO or THROW, that is the target of a jump instruction, or that
138      * starts an exception handler block. The visited types must describe the
139      * values of the local variables and of the operand stack elements <i>just
140      * before</i> <b>i</b> is executed. <br> <br> (*) this is mandatory only
141      * for classes whose version is greater than or equal to
142      * {@link Opcodes#V1_6 V1_6}. <br> <br> Packed frames are basically
143      * "deltas" from the state of the previous frame (very first frame is
144      * implicitly defined by the method's parameters and access flags): <ul>
145      * <li>{@link Opcodes#F_SAME} representing frame with exactly the same
146      * locals as the previous frame and with the empty stack.</li> <li>{@link Opcodes#F_SAME1}
147      * representing frame with exactly the same locals as the previous frame and
148      * with single value on the stack (<code>nStack</code> is 1 and
149      * <code>stack[0]</code> contains value for the type of the stack item).</li>
150      * <li>{@link Opcodes#F_APPEND} representing frame with current locals are
151      * the same as the locals in the previous frame, except that additional
152      * locals are defined (<code>nLocal</code> is 1, 2 or 3 and
153      * <code>local</code> elements contains values representing added types).</li>
154      * <li>{@link Opcodes#F_CHOP} representing frame with current locals are
155      * the same as the locals in the previous frame, except that the last 1-3
156      * locals are absent and with the empty stack (<code>nLocals</code> is 1,
157      * 2 or 3). </li> <li>{@link Opcodes#F_FULL} representing complete frame
158      * data.</li> </li> </ul>
159      *
160      * @param type the type of this stack map frame. Must be
161      *        {@link Opcodes#F_NEW} for expanded frames, or
162      *        {@link Opcodes#F_FULL}, {@link Opcodes#F_APPEND},
163      *        {@link Opcodes#F_CHOP}, {@link Opcodes#F_SAME} or
164      *        {@link Opcodes#F_APPEND}, {@link Opcodes#F_SAME1} for compressed
165      *        frames.
166      * @param nLocal the number of local variables in the visited frame.
167      * @param local the local variable types in this frame. This array must not
168      *        be modified. Primitive types are represented by
169      *        {@link Opcodes#TOP}, {@link Opcodes#INTEGER},
170      *        {@link Opcodes#FLOAT}, {@link Opcodes#LONG},
171      *        {@link Opcodes#DOUBLE},{@link Opcodes#NULL} or
172      *        {@link Opcodes#UNINITIALIZED_THIS} (long and double are
173      *        represented by a single element). Reference types are represented
174      *        by String objects (representing internal names), and uninitialized
175      *        types by Label objects (this label designates the NEW instruction
176      *        that created this uninitialized value).
177      * @param nStack the number of operand stack elements in the visited frame.
178      * @param stack the operand stack types in this frame. This array must not
179      *        be modified. Its content has the same format as the "local" array.
180      */
181     void visitFrame(
182         int type,
183         int nLocal,
184         Object[] local,
185         int nStack,
186         Object[] stack);
187 
188     // -------------------------------------------------------------------------
189     // Normal instructions
190     // -------------------------------------------------------------------------
191 
192     /**
193      * Visits a zero operand instruction.
194      *
195      * @param opcode the opcode of the instruction to be visited. This opcode is
196      *        either NOP, ACONST_NULL, ICONST_M1, ICONST_0, ICONST_1, ICONST_2,
197      *        ICONST_3, ICONST_4, ICONST_5, LCONST_0, LCONST_1, FCONST_0,
198      *        FCONST_1, FCONST_2, DCONST_0, DCONST_1, IALOAD, LALOAD, FALOAD,
199      *        DALOAD, AALOAD, BALOAD, CALOAD, SALOAD, IASTORE, LASTORE, FASTORE,
200      *        DASTORE, AASTORE, BASTORE, CASTORE, SASTORE, POP, POP2, DUP,
201      *        DUP_X1, DUP_X2, DUP2, DUP2_X1, DUP2_X2, SWAP, IADD, LADD, FADD,
202      *        DADD, ISUB, LSUB, FSUB, DSUB, IMUL, LMUL, FMUL, DMUL, IDIV, LDIV,
203      *        FDIV, DDIV, IREM, LREM, FREM, DREM, INEG, LNEG, FNEG, DNEG, ISHL,
204      *        LSHL, ISHR, LSHR, IUSHR, LUSHR, IAND, LAND, IOR, LOR, IXOR, LXOR,
205      *        I2L, I2F, I2D, L2I, L2F, L2D, F2I, F2L, F2D, D2I, D2L, D2F, I2B,
206      *        I2C, I2S, LCMP, FCMPL, FCMPG, DCMPL, DCMPG, IRETURN, LRETURN,
207      *        FRETURN, DRETURN, ARETURN, RETURN, ARRAYLENGTH, ATHROW,
208      *        MONITORENTER, or MONITOREXIT.
209      */
210     void visitInsn(int opcode);
211 
212     /**
213      * Visits an instruction with a single int operand.
214      *
215      * @param opcode the opcode of the instruction to be visited. This opcode is
216      *        either BIPUSH, SIPUSH or NEWARRAY.
217      * @param operand the operand of the instruction to be visited.<br> When
218      *        opcode is BIPUSH, operand value should be between Byte.MIN_VALUE
219      *        and Byte.MAX_VALUE.<br> When opcode is SIPUSH, operand value
220      *        should be between Short.MIN_VALUE and Short.MAX_VALUE.<br> When
221      *        opcode is NEWARRAY, operand value should be one of
222      *        {@link Opcodes#T_BOOLEAN}, {@link Opcodes#T_CHAR},
223      *        {@link Opcodes#T_FLOAT}, {@link Opcodes#T_DOUBLE},
224      *        {@link Opcodes#T_BYTE}, {@link Opcodes#T_SHORT},
225      *        {@link Opcodes#T_INT} or {@link Opcodes#T_LONG}.
226      */
227     void visitIntInsn(int opcode, int operand);
228 
229     /**
230      * Visits a local variable instruction. A local variable instruction is an
231      * instruction that loads or stores the value of a local variable.
232      *
233      * @param opcode the opcode of the local variable instruction to be visited.
234      *        This opcode is either ILOAD, LLOAD, FLOAD, DLOAD, ALOAD, ISTORE,
235      *        LSTORE, FSTORE, DSTORE, ASTORE or RET.
236      * @param var the operand of the instruction to be visited. This operand is
237      *        the index of a local variable.
238      */
239     void visitVarInsn(int opcode, int var);
240 
241     /**
242      * Visits a type instruction. A type instruction is an instruction that
243      * takes the internal name of a class as parameter.
244      *
245      * @param opcode the opcode of the type instruction to be visited. This
246      *        opcode is either NEW, ANEWARRAY, CHECKCAST or INSTANCEOF.
247      * @param type the operand of the instruction to be visited. This operand
248      *        must be the internal name of an object or array class (see {@link
249      *        Type#getInternalName() getInternalName}).
250      */
251     void visitTypeInsn(int opcode, String type);
252 
253     /**
254      * Visits a field instruction. A field instruction is an instruction that
255      * loads or stores the value of a field of an object.
256      *
257      * @param opcode the opcode of the type instruction to be visited. This
258      *        opcode is either GETSTATIC, PUTSTATIC, GETFIELD or PUTFIELD.
259      * @param owner the internal name of the field's owner class (see {@link
260      *        Type#getInternalName() getInternalName}).
261      * @param name the field's name.
262      * @param desc the field's descriptor (see {@link Type Type}).
263      */
264     void visitFieldInsn(int opcode, String owner, String name, String desc);
265 
266     /**
267      * Visits a method instruction. A method instruction is an instruction that
268      * invokes a method.
269      *
270      * @param opcode the opcode of the type instruction to be visited. This
271      *        opcode is either INVOKEVIRTUAL, INVOKESPECIAL, INVOKESTATIC or
272      *        INVOKEINTERFACE.
273      * @param owner the internal name of the method's owner class (see {@link
274      *        Type#getInternalName() getInternalName}).
275      * @param name the method's name.
276      * @param desc the method's descriptor (see {@link Type Type}).
277      */
278     void visitMethodInsn(int opcode, String owner, String name, String desc);
279 
280     /**
281      * Visits a jump instruction. A jump instruction is an instruction that may
282      * jump to another instruction.
283      *
284      * @param opcode the opcode of the type instruction to be visited. This
285      *        opcode is either IFEQ, IFNE, IFLT, IFGE, IFGT, IFLE, IF_ICMPEQ,
286      *        IF_ICMPNE, IF_ICMPLT, IF_ICMPGE, IF_ICMPGT, IF_ICMPLE, IF_ACMPEQ,
287      *        IF_ACMPNE, GOTO, JSR, IFNULL or IFNONNULL.
288      * @param label the operand of the instruction to be visited. This operand
289      *        is a label that designates the instruction to which the jump
290      *        instruction may jump.
291      */
292     void visitJumpInsn(int opcode, Label label);
293 
294     /**
295      * Visits a label. A label designates the instruction that will be visited
296      * just after it.
297      *
298      * @param label a {@link Label Label} object.
299      */
300     void visitLabel(Label label);
301 
302     // -------------------------------------------------------------------------
303     // Special instructions
304     // -------------------------------------------------------------------------
305 
306     /**
307      * Visits a LDC instruction.
308      *
309      * @param cst the constant to be loaded on the stack. This parameter must be
310      *        a non null {@link Integer}, a {@link Float}, a {@link Long}, a
311      *        {@link Double} a {@link String} (or a {@link Type} for
312      *        <tt>.class</tt> constants, for classes whose version is 49.0 or
313      *        more).
314      */
315     void visitLdcInsn(Object cst);
316 
317     /**
318      * Visits an IINC instruction.
319      *
320      * @param var index of the local variable to be incremented.
321      * @param increment amount to increment the local variable by.
322      */
323     void visitIincInsn(int var, int increment);
324 
325     /**
326      * Visits a TABLESWITCH instruction.
327      *
328      * @param min the minimum key value.
329      * @param max the maximum key value.
330      * @param dflt beginning of the default handler block.
331      * @param labels beginnings of the handler blocks. <tt>labels[i]</tt> is
332      *        the beginning of the handler block for the <tt>min + i</tt> key.
333      */
334     void visitTableSwitchInsn(int min, int max, Label dflt, Label[] labels);
335 
336     /**
337      * Visits a LOOKUPSWITCH instruction.
338      *
339      * @param dflt beginning of the default handler block.
340      * @param keys the values of the keys.
341      * @param labels beginnings of the handler blocks. <tt>labels[i]</tt> is
342      *        the beginning of the handler block for the <tt>keys[i]</tt> key.
343      */
344     void visitLookupSwitchInsn(Label dflt, int[] keys, Label[] labels);
345 
346     /**
347      * Visits a MULTIANEWARRAY instruction.
348      *
349      * @param desc an array type descriptor (see {@link Type Type}).
350      * @param dims number of dimensions of the array to allocate.
351      */
352     void visitMultiANewArrayInsn(String desc, int dims);
353 
354     // -------------------------------------------------------------------------
355     // Exceptions table entries, debug information, max stack and max locals
356     // -------------------------------------------------------------------------
357 
358     /**
359      * Visits a try catch block.
360      *
361      * @param start beginning of the exception handler's scope (inclusive).
362      * @param end end of the exception handler's scope (exclusive).
363      * @param handler beginning of the exception handler's code.
364      * @param type internal name of the type of exceptions handled by the
365      *        handler, or <tt>null</tt> to catch any exceptions (for "finally"
366      *        blocks).
367      * @throws IllegalArgumentException if one of the labels has already been
368      *         visited by this visitor (by the {@link #visitLabel visitLabel}
369      *         method).
370      */
371     void visitTryCatchBlock(Label start, Label end, Label handler, String type);
372 
373     /**
374      * Visits a local variable declaration.
375      *
376      * @param name the name of a local variable.
377      * @param desc the type descriptor of this local variable.
378      * @param signature the type signature of this local variable. May be
379      *        <tt>null</tt> if the local variable type does not use generic
380      *        types.
381      * @param start the first instruction corresponding to the scope of this
382      *        local variable (inclusive).
383      * @param end the last instruction corresponding to the scope of this local
384      *        variable (exclusive).
385      * @param index the local variable's index.
386      * @throws IllegalArgumentException if one of the labels has not already
387      *         been visited by this visitor (by the
388      *         {@link #visitLabel visitLabel} method).
389      */
390     void visitLocalVariable(
391         String name,
392         String desc,
393         String signature,
394         Label start,
395         Label end,
396         int index);
397 
398     /**
399      * Visits a line number declaration.
400      *
401      * @param line a line number. This number refers to the source file from
402      *        which the class was compiled.
403      * @param start the first instruction corresponding to this line number.
404      * @throws IllegalArgumentException if <tt>start</tt> has not already been
405      *         visited by this visitor (by the {@link #visitLabel visitLabel}
406      *         method).
407      */
408     void visitLineNumber(int line, Label start);
409 
410     /**
411      * Visits the maximum stack size and the maximum number of local variables
412      * of the method.
413      *
414      * @param maxStack maximum stack size of the method.
415      * @param maxLocals maximum number of local variables for the method.
416      */
417     void visitMaxs(int maxStack, int maxLocals);
418 
419     /**
420      * Visits the end of the method. This method, which is the last one to be
421      * called, is used to inform the visitor that all the annotations and
422      * attributes of the method have been visited.
423      */
424     void visitEnd();
425 }