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17 package org.apache.bcel.util;
18
19 import java.io.PrintWriter  ;
20 import java.util.ArrayList ;
21 import java.util.HashMap ;
22 import java.util.Iterator ;
23 import java.util.List ;
24 import java.util.Locale ;
25 import java.util.Map ;
26 import org.apache.bcel.Constants;
27 import org.apache.bcel.classfile.Utility;
28 import org.apache.bcel.generic.AllocationInstruction;
29 import org.apache.bcel.generic.ArrayInstruction;
30 import org.apache.bcel.generic.ArrayType;
31 import org.apache.bcel.generic.BranchHandle;
32 import org.apache.bcel.generic.BranchInstruction;
33 import org.apache.bcel.generic.CHECKCAST;
34 import org.apache.bcel.generic.CPInstruction;
35 import org.apache.bcel.generic.CodeExceptionGen;
36 import org.apache.bcel.generic.ConstantPoolGen;
37 import org.apache.bcel.generic.ConstantPushInstruction;
38 import org.apache.bcel.generic.EmptyVisitor;
39 import org.apache.bcel.generic.FieldInstruction;
40 import org.apache.bcel.generic.IINC;
41 import org.apache.bcel.generic.INSTANCEOF;
42 import org.apache.bcel.generic.Instruction;
43 import org.apache.bcel.generic.InstructionConstants;
44 import org.apache.bcel.generic.InstructionHandle;
45 import org.apache.bcel.generic.InvokeInstruction;
46 import org.apache.bcel.generic.LDC;
47 import org.apache.bcel.generic.LDC2_W;
48 import org.apache.bcel.generic.LocalVariableInstruction;
49 import org.apache.bcel.generic.MULTIANEWARRAY;
50 import org.apache.bcel.generic.MethodGen;
51 import org.apache.bcel.generic.NEWARRAY;
52 import org.apache.bcel.generic.ObjectType;
53 import org.apache.bcel.generic.RET;
54 import org.apache.bcel.generic.ReturnInstruction;
55 import org.apache.bcel.generic.Select;
56 import org.apache.bcel.generic.Type;
57
58
66 class BCELFactory extends EmptyVisitor {
67
68 private MethodGen _mg;
69 private PrintWriter _out;
70 private ConstantPoolGen _cp;
71
72
73 BCELFactory(MethodGen mg, PrintWriter out) {
74 _mg = mg;
75 _cp = mg.getConstantPool();
76 _out = out;
77 }
78
79 private Map branch_map = new HashMap ();
81
82 public void start() {
83 if (!_mg.isAbstract() && !_mg.isNative()) {
84 for (InstructionHandle ih = _mg.getInstructionList().getStart(); ih != null; ih = ih
85 .getNext()) {
86 Instruction i = ih.getInstruction();
87 if (i instanceof BranchInstruction) {
88 branch_map.put(i, ih); }
90 if (ih.hasTargeters()) {
91 if (i instanceof BranchInstruction) {
92 _out.println(" InstructionHandle ih_" + ih.getPosition() + ";");
93 } else {
94 _out.print(" InstructionHandle ih_" + ih.getPosition() + " = ");
95 }
96 } else {
97 _out.print(" ");
98 }
99 if (!visitInstruction(i)) {
100 i.accept(this);
101 }
102 }
103 updateBranchTargets();
104 updateExceptionHandlers();
105 }
106 }
107
108
109 private boolean visitInstruction( Instruction i ) {
110 short opcode = i.getOpcode();
111 if ((InstructionConstants.INSTRUCTIONS[opcode] != null)
112 && !(i instanceof ConstantPushInstruction) && !(i instanceof ReturnInstruction)) { _out.println("il.append(InstructionConstants."
114 + i.getName().toUpperCase(Locale.ENGLISH) + ");");
115 return true;
116 }
117 return false;
118 }
119
120
121 public void visitLocalVariableInstruction( LocalVariableInstruction i ) {
122 short opcode = i.getOpcode();
123 Type type = i.getType(_cp);
124 if (opcode == Constants.IINC) {
125 _out.println("il.append(new IINC(" + i.getIndex() + ", " + ((IINC) i).getIncrement()
126 + "));");
127 } else {
128 String kind = (opcode < Constants.ISTORE) ? "Load" : "Store";
129 _out.println("il.append(_factory.create" + kind + "(" + BCELifier.printType(type)
130 + ", " + i.getIndex() + "));");
131 }
132 }
133
134
135 public void visitArrayInstruction( ArrayInstruction i ) {
136 short opcode = i.getOpcode();
137 Type type = i.getType(_cp);
138 String kind = (opcode < Constants.IASTORE) ? "Load" : "Store";
139 _out.println("il.append(_factory.createArray" + kind + "(" + BCELifier.printType(type)
140 + "));");
141 }
142
143
144 public void visitFieldInstruction( FieldInstruction i ) {
145 short opcode = i.getOpcode();
146 String class_name = i.getClassName(_cp);
147 String field_name = i.getFieldName(_cp);
148 Type type = i.getFieldType(_cp);
149 _out.println("il.append(_factory.createFieldAccess(\"" + class_name + "\", \"" + field_name
150 + "\", " + BCELifier.printType(type) + ", " + "Constants."
151 + Constants.OPCODE_NAMES[opcode].toUpperCase(Locale.ENGLISH) + "));");
152 }
153
154
155 public void visitInvokeInstruction( InvokeInstruction i ) {
156 short opcode = i.getOpcode();
157 String class_name = i.getClassName(_cp);
158 String method_name = i.getMethodName(_cp);
159 Type type = i.getReturnType(_cp);
160 Type[] arg_types = i.getArgumentTypes(_cp);
161 _out.println("il.append(_factory.createInvoke(\"" + class_name + "\", \"" + method_name
162 + "\", " + BCELifier.printType(type) + ", "
163 + BCELifier.printArgumentTypes(arg_types) + ", " + "Constants."
164 + Constants.OPCODE_NAMES[opcode].toUpperCase(Locale.ENGLISH) + "));");
165 }
166
167
168 public void visitAllocationInstruction( AllocationInstruction i ) {
169 Type type;
170 if (i instanceof CPInstruction) {
171 type = ((CPInstruction) i).getType(_cp);
172 } else {
173 type = ((NEWARRAY) i).getType();
174 }
175 short opcode = ((Instruction) i).getOpcode();
176 int dim = 1;
177 switch (opcode) {
178 case Constants.NEW:
179 _out.println("il.append(_factory.createNew(\"" + ((ObjectType) type).getClassName()
180 + "\"));");
181 break;
182 case Constants.MULTIANEWARRAY:
183 dim = ((MULTIANEWARRAY) i).getDimensions();
184 case Constants.ANEWARRAY:
185 case Constants.NEWARRAY:
186 if (type instanceof ArrayType) {
187 type = ((ArrayType) type).getBasicType();
188 }
189 _out.println("il.append(_factory.createNewArray(" + BCELifier.printType(type)
190 + ", (short) " + dim + "));");
191 break;
192 default:
193 throw new RuntimeException ("Oops: " + opcode);
194 }
195 }
196
197
198 private void createConstant( Object value ) {
199 String embed = value.toString();
200 if (value instanceof String ) {
201 embed = '"' + Utility.convertString(value.toString()) + '"';
202 } else if (value instanceof Character ) {
203 embed = "(char)0x" + Integer.toHexString(((Character ) value).charValue());
204 }
205 _out.println("il.append(new PUSH(_cp, " + embed + "));");
206 }
207
208
209 public void visitLDC( LDC i ) {
210 createConstant(i.getValue(_cp));
211 }
212
213
214 public void visitLDC2_W( LDC2_W i ) {
215 createConstant(i.getValue(_cp));
216 }
217
218
219 public void visitConstantPushInstruction( ConstantPushInstruction i ) {
220 createConstant(i.getValue());
221 }
222
223
224 public void visitINSTANCEOF( INSTANCEOF i ) {
225 Type type = i.getType(_cp);
226 _out.println("il.append(new INSTANCEOF(_cp.addClass(" + BCELifier.printType(type) + ")));");
227 }
228
229
230 public void visitCHECKCAST( CHECKCAST i ) {
231 Type type = i.getType(_cp);
232 _out.println("il.append(_factory.createCheckCast(" + BCELifier.printType(type) + "));");
233 }
234
235
236 public void visitReturnInstruction( ReturnInstruction i ) {
237 Type type = i.getType(_cp);
238 _out.println("il.append(_factory.createReturn(" + BCELifier.printType(type) + "));");
239 }
240
241 private List branches = new ArrayList ();
243
244
245 public void visitBranchInstruction( BranchInstruction bi ) {
246 BranchHandle bh = (BranchHandle) branch_map.get(bi);
247 int pos = bh.getPosition();
248 String name = bi.getName() + "_" + pos;
249 if (bi instanceof Select) {
250 Select s = (Select) bi;
251 branches.add(bi);
252 StringBuffer args = new StringBuffer ("new int[] { ");
253 int[] matchs = s.getMatchs();
254 for (int i = 0; i < matchs.length; i++) {
255 args.append(matchs[i]);
256 if (i < matchs.length - 1) {
257 args.append(", ");
258 }
259 }
260 args.append(" }");
261 _out.print("Select " + name + " = new " + bi.getName().toUpperCase(Locale.ENGLISH)
262 + "(" + args + ", new InstructionHandle[] { ");
263 for (int i = 0; i < matchs.length; i++) {
264 _out.print("null");
265 if (i < matchs.length - 1) {
266 _out.print(", ");
267 }
268 }
269 _out.println(" }, null);");
270 } else {
271 int t_pos = bh.getTarget().getPosition();
272 String target;
273 if (pos > t_pos) {
274 target = "ih_" + t_pos;
275 } else {
276 branches.add(bi);
277 target = "null";
278 }
279 _out.println(" BranchInstruction " + name + " = _factory.createBranchInstruction("
280 + "Constants." + bi.getName().toUpperCase(Locale.ENGLISH) + ", " + target
281 + ");");
282 }
283 if (bh.hasTargeters()) {
284 _out.println(" ih_" + pos + " = il.append(" + name + ");");
285 } else {
286 _out.println(" il.append(" + name + ");");
287 }
288 }
289
290
291 public void visitRET( RET i ) {
292 _out.println("il.append(new RET(" + i.getIndex() + ")));");
293 }
294
295
296 private void updateBranchTargets() {
297 for (Iterator i = branches.iterator(); i.hasNext();) {
298 BranchInstruction bi = (BranchInstruction) i.next();
299 BranchHandle bh = (BranchHandle) branch_map.get(bi);
300 int pos = bh.getPosition();
301 String name = bi.getName() + "_" + pos;
302 int t_pos = bh.getTarget().getPosition();
303 _out.println(" " + name + ".setTarget(ih_" + t_pos + ");");
304 if (bi instanceof Select) {
305 InstructionHandle[] ihs = ((Select) bi).getTargets();
306 for (int j = 0; j < ihs.length; j++) {
307 t_pos = ihs[j].getPosition();
308 _out.println(" " + name + ".setTarget(" + j + ", ih_" + t_pos + ");");
309 }
310 }
311 }
312 }
313
314
315 private void updateExceptionHandlers() {
316 CodeExceptionGen[] handlers = _mg.getExceptionHandlers();
317 for (int i = 0; i < handlers.length; i++) {
318 CodeExceptionGen h = handlers[i];
319 String type = (h.getCatchType() == null) ? "null" : BCELifier.printType(h
320 .getCatchType());
321 _out.println(" method.addExceptionHandler(" + "ih_" + h.getStartPC().getPosition()
322 + ", " + "ih_" + h.getEndPC().getPosition() + ", " + "ih_"
323 + h.getHandlerPC().getPosition() + ", " + type + ");");
324 }
325 }
326 }
327 |
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