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Java > Open Source Codes > proguard > classfile > instruction > InstructionFactory


1 /*
2  * ProGuard -- shrinking, optimization, obfuscation, and preverification
3  * of Java bytecode.
4  *
5  * Copyright (c) 2002-2007 Eric Lafortune (eric@graphics.cornell.edu)
6  *
7  * This program is free software; you can redistribute it and/or modify it
8  * under the terms of the GNU General Public License as published by the Free
9  * Software Foundation; either version 2 of the License, or (at your option)
10  * any later version.
11  *
12  * This program is distributed in the hope that it will be useful, but WITHOUT
13  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
14  * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
15  * more details.
16  *
17  * You should have received a copy of the GNU General Public License along
18  * with this program; if not, write to the Free Software Foundation, Inc.,
19  * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
20  */
21 package proguard.classfile.instruction;
22
23 /**
24  * This class provides methods to create and reuse Instruction objects.
25  *
26  * @author Eric Lafortune
27  */
28 public class InstructionFactory
29 {
30     /**
31      * Creates a new Instruction from the data in the byte array, starting
32      * at the given index.
33      */
34     public static Instruction create(byte[] code, int offset)
35     {
36         Instruction instruction;
37
38         int index = offset;
39         byte opcode = code[index++];
40
41         boolean wide = false;
42         if (opcode == InstructionConstants.OP_WIDE)
43         {
44             opcode = code[index++];
45             wide = true;
46         }
47
48         switch (opcode)
49         {
50             // Simple instructions.
51 case InstructionConstants.OP_NOP:
52             case InstructionConstants.OP_ACONST_NULL:
53             case InstructionConstants.OP_ICONST_M1:
54             case InstructionConstants.OP_ICONST_0:
55             case InstructionConstants.OP_ICONST_1:
56             case InstructionConstants.OP_ICONST_2:
57             case InstructionConstants.OP_ICONST_3:
58             case InstructionConstants.OP_ICONST_4:
59             case InstructionConstants.OP_ICONST_5:
60             case InstructionConstants.OP_LCONST_0:
61             case InstructionConstants.OP_LCONST_1:
62             case InstructionConstants.OP_FCONST_0:
63             case InstructionConstants.OP_FCONST_1:
64             case InstructionConstants.OP_FCONST_2:
65             case InstructionConstants.OP_DCONST_0:
66             case InstructionConstants.OP_DCONST_1:
67
68             case InstructionConstants.OP_BIPUSH:
69             case InstructionConstants.OP_SIPUSH:
70
71             case InstructionConstants.OP_IALOAD:
72             case InstructionConstants.OP_LALOAD:
73             case InstructionConstants.OP_FALOAD:
74             case InstructionConstants.OP_DALOAD:
75             case InstructionConstants.OP_AALOAD:
76             case InstructionConstants.OP_BALOAD:
77             case InstructionConstants.OP_CALOAD:
78             case InstructionConstants.OP_SALOAD:
79
80             case InstructionConstants.OP_IASTORE:
81             case InstructionConstants.OP_LASTORE:
82             case InstructionConstants.OP_FASTORE:
83             case InstructionConstants.OP_DASTORE:
84             case InstructionConstants.OP_AASTORE:
85             case InstructionConstants.OP_BASTORE:
86             case InstructionConstants.OP_CASTORE:
87             case InstructionConstants.OP_SASTORE:
88             case InstructionConstants.OP_POP:
89             case InstructionConstants.OP_POP2:
90             case InstructionConstants.OP_DUP:
91             case InstructionConstants.OP_DUP_X1:
92             case InstructionConstants.OP_DUP_X2:
93             case InstructionConstants.OP_DUP2:
94             case InstructionConstants.OP_DUP2_X1:
95             case InstructionConstants.OP_DUP2_X2:
96             case InstructionConstants.OP_SWAP:
97             case InstructionConstants.OP_IADD:
98             case InstructionConstants.OP_LADD:
99             case InstructionConstants.OP_FADD:
100             case InstructionConstants.OP_DADD:
101             case InstructionConstants.OP_ISUB:
102             case InstructionConstants.OP_LSUB:
103             case InstructionConstants.OP_FSUB:
104             case InstructionConstants.OP_DSUB:
105             case InstructionConstants.OP_IMUL:
106             case InstructionConstants.OP_LMUL:
107             case InstructionConstants.OP_FMUL:
108             case InstructionConstants.OP_DMUL:
109             case InstructionConstants.OP_IDIV:
110             case InstructionConstants.OP_LDIV:
111             case InstructionConstants.OP_FDIV:
112             case InstructionConstants.OP_DDIV:
113             case InstructionConstants.OP_IREM:
114             case InstructionConstants.OP_LREM:
115             case InstructionConstants.OP_FREM:
116             case InstructionConstants.OP_DREM:
117             case InstructionConstants.OP_INEG:
118             case InstructionConstants.OP_LNEG:
119             case InstructionConstants.OP_FNEG:
120             case InstructionConstants.OP_DNEG:
121             case InstructionConstants.OP_ISHL:
122             case InstructionConstants.OP_LSHL:
123             case InstructionConstants.OP_ISHR:
124             case InstructionConstants.OP_LSHR:
125             case InstructionConstants.OP_IUSHR:
126             case InstructionConstants.OP_LUSHR:
127             case InstructionConstants.OP_IAND:
128             case InstructionConstants.OP_LAND:
129             case InstructionConstants.OP_IOR:
130             case InstructionConstants.OP_LOR:
131             case InstructionConstants.OP_IXOR:
132             case InstructionConstants.OP_LXOR:
133
134             case InstructionConstants.OP_I2L:
135             case InstructionConstants.OP_I2F:
136             case InstructionConstants.OP_I2D:
137             case InstructionConstants.OP_L2I:
138             case InstructionConstants.OP_L2F:
139             case InstructionConstants.OP_L2D:
140             case InstructionConstants.OP_F2I:
141             case InstructionConstants.OP_F2L:
142             case InstructionConstants.OP_F2D:
143             case InstructionConstants.OP_D2I:
144             case InstructionConstants.OP_D2L:
145             case InstructionConstants.OP_D2F:
146             case InstructionConstants.OP_I2B:
147             case InstructionConstants.OP_I2C:
148             case InstructionConstants.OP_I2S:
149             case InstructionConstants.OP_LCMP:
150             case InstructionConstants.OP_FCMPL:
151             case InstructionConstants.OP_FCMPG:
152             case InstructionConstants.OP_DCMPL:
153             case InstructionConstants.OP_DCMPG:
154
155             case InstructionConstants.OP_IRETURN:
156             case InstructionConstants.OP_LRETURN:
157             case InstructionConstants.OP_FRETURN:
158             case InstructionConstants.OP_DRETURN:
159             case InstructionConstants.OP_ARETURN:
160             case InstructionConstants.OP_RETURN:
161
162             case InstructionConstants.OP_NEWARRAY:
163             case InstructionConstants.OP_ARRAYLENGTH:
164             case InstructionConstants.OP_ATHROW:
165
166             case InstructionConstants.OP_MONITORENTER:
167             case InstructionConstants.OP_MONITOREXIT:
168                 instruction = new SimpleInstruction();
169                 break;
170
171             // Instructions with a contant pool index.
172 case InstructionConstants.OP_LDC:
173             case InstructionConstants.OP_LDC_W:
174             case InstructionConstants.OP_LDC2_W:
175
176             case InstructionConstants.OP_GETSTATIC:
177             case InstructionConstants.OP_PUTSTATIC:
178             case InstructionConstants.OP_GETFIELD:
179             case InstructionConstants.OP_PUTFIELD:
180
181             case InstructionConstants.OP_INVOKEVIRTUAL:
182             case InstructionConstants.OP_INVOKESPECIAL:
183             case InstructionConstants.OP_INVOKESTATIC:
184             case InstructionConstants.OP_INVOKEINTERFACE:
185
186             case InstructionConstants.OP_NEW:
187             case InstructionConstants.OP_ANEWARRAY:
188             case InstructionConstants.OP_CHECKCAST:
189             case InstructionConstants.OP_INSTANCEOF:
190             case InstructionConstants.OP_MULTIANEWARRAY:
191                 instruction = new ConstantInstruction();
192                 break;
193
194             // Instructions with a local variable index.
195 case InstructionConstants.OP_ILOAD:
196             case InstructionConstants.OP_LLOAD:
197             case InstructionConstants.OP_FLOAD:
198             case InstructionConstants.OP_DLOAD:
199             case InstructionConstants.OP_ALOAD:
200             case InstructionConstants.OP_ILOAD_0:
201             case InstructionConstants.OP_ILOAD_1:
202             case InstructionConstants.OP_ILOAD_2:
203             case InstructionConstants.OP_ILOAD_3:
204             case InstructionConstants.OP_LLOAD_0:
205             case InstructionConstants.OP_LLOAD_1:
206             case InstructionConstants.OP_LLOAD_2:
207             case InstructionConstants.OP_LLOAD_3:
208             case InstructionConstants.OP_FLOAD_0:
209             case InstructionConstants.OP_FLOAD_1:
210             case InstructionConstants.OP_FLOAD_2:
211             case InstructionConstants.OP_FLOAD_3:
212             case InstructionConstants.OP_DLOAD_0:
213             case InstructionConstants.OP_DLOAD_1:
214             case InstructionConstants.OP_DLOAD_2:
215             case InstructionConstants.OP_DLOAD_3:
216             case InstructionConstants.OP_ALOAD_0:
217             case InstructionConstants.OP_ALOAD_1:
218             case InstructionConstants.OP_ALOAD_2:
219             case InstructionConstants.OP_ALOAD_3:
220
221             case InstructionConstants.OP_ISTORE:
222             case InstructionConstants.OP_LSTORE:
223             case InstructionConstants.OP_FSTORE:
224             case InstructionConstants.OP_DSTORE:
225             case InstructionConstants.OP_ASTORE:
226             case InstructionConstants.OP_ISTORE_0:
227             case InstructionConstants.OP_ISTORE_1:
228             case InstructionConstants.OP_ISTORE_2:
229             case InstructionConstants.OP_ISTORE_3:
230             case InstructionConstants.OP_LSTORE_0:
231             case InstructionConstants.OP_LSTORE_1:
232             case InstructionConstants.OP_LSTORE_2:
233             case InstructionConstants.OP_LSTORE_3:
234             case InstructionConstants.OP_FSTORE_0:
235             case InstructionConstants.OP_FSTORE_1:
236             case InstructionConstants.OP_FSTORE_2:
237             case InstructionConstants.OP_FSTORE_3:
238             case InstructionConstants.OP_DSTORE_0:
239             case InstructionConstants.OP_DSTORE_1:
240             case InstructionConstants.OP_DSTORE_2:
241             case InstructionConstants.OP_DSTORE_3:
242             case InstructionConstants.OP_ASTORE_0:
243             case InstructionConstants.OP_ASTORE_1:
244             case InstructionConstants.OP_ASTORE_2:
245             case InstructionConstants.OP_ASTORE_3:
246
247             case InstructionConstants.OP_IINC:
248
249             case InstructionConstants.OP_RET:
250                 instruction = new VariableInstruction(wide);
251                 break;
252
253             // Instructions with a branch offset operand.
254 case InstructionConstants.OP_IFEQ:
255             case InstructionConstants.OP_IFNE:
256             case InstructionConstants.OP_IFLT:
257             case InstructionConstants.OP_IFGE:
258             case InstructionConstants.OP_IFGT:
259             case InstructionConstants.OP_IFLE:
260             case InstructionConstants.OP_IFICMPEQ:
261             case InstructionConstants.OP_IFICMPNE:
262             case InstructionConstants.OP_IFICMPLT:
263             case InstructionConstants.OP_IFICMPGE:
264             case InstructionConstants.OP_IFICMPGT:
265             case InstructionConstants.OP_IFICMPLE:
266             case InstructionConstants.OP_IFACMPEQ:
267             case InstructionConstants.OP_IFACMPNE:
268             case InstructionConstants.OP_GOTO:
269             case InstructionConstants.OP_JSR:
270
271             case InstructionConstants.OP_IFNULL:
272             case InstructionConstants.OP_IFNONNULL:
273
274             case InstructionConstants.OP_GOTO_W:
275             case InstructionConstants.OP_JSR_W:
276                 instruction = new BranchInstruction();
277                 break;
278
279             // The tableswitch instruction.
280 case InstructionConstants.OP_TABLESWITCH:
281                 instruction = new TableSwitchInstruction();
282                 break;
283
284             // The lookupswitch instruction.
285 case InstructionConstants.OP_LOOKUPSWITCH:
286                 instruction = new LookUpSwitchInstruction();
287                 break;
288
289             default:
290                 throw new IllegalArgumentException JavaDoc("Unknown instruction opcode ["+opcode+"] at offset "+offset);
291         }
292
293         instruction.opcode = opcode;
294
295         instruction.readInfo(code, index);
296
297         return instruction;
298     }
299 }
300
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