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 */
30package com.sleepycat.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 */
47public 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     */
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     */
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     */
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     */
91    void visitAttribute(Attribute attr);
92
93    /**
94     * Starts the visit of the method's code, if any (i.e. non abstract method).
95     */
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     */
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     */
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     */
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     */
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     */
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     */
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     */
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     */
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     */
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     */
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     */
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     */
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     */
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     */
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     */
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     */
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     */
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     */
333    void visitEnd();
334}
335