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1
24
25 package org.aspectj.compiler.crosscuts.ast;
26
27 import javax.swing.JPanel  ;
28
29 import org.aspectj.compiler.base.FlowCheckerPass;
30 import org.aspectj.compiler.base.ast.*;
31 import org.aspectj.compiler.crosscuts.joinpoints.*;
32 import org.aspectj.compiler.base.JavaCompiler;
33
34
38
39
40 public class AfterReturningAdviceDec extends AdviceDec {
41 protected String getAdviceKind() { return "afterReturning"; }
42
43 protected boolean isAfterAdvice() { return true; }
44
45 private static final String CONSTRUCTOR_EXECUTION_BINDING_CHANGE =
46 "return value will bind to null, use 'this' pointcut to bind executing object\n" +
47 " behavior change to fix compiler bug in 1.0.3 and earlier";
48
49 private static final String VOID_RETURN_CHANGE =
50 "will not match this joinpoint, use Object return type in advice if match desired\n" +
51 " behavior change to fix compiler bug in 1.0.3 and earlier";
52
53 protected Stmts wrapStmts(Stmts stmts, AdvicePlan plan) {
54 JoinPoint jp = plan.getJoinPoint();
55 FormalDec formal = getExtraFormal();
56
57 if (jp instanceof ExceptionHandlerJp) {
58 showWarning("can't apply after returning advice to exception handler join points (compiler limitation)");
59 jp.getSourceLocation().showWarning(
60 "trying to apply above after returning advice to execution of this exception handler");
61 return stmts;
62 }
63 if (jp.getResultType().isVoid()) {
64 if (formal != null && !formal.getType().isObject()) {
65 jp.showWarning(this, VOID_RETURN_CHANGE);
66 return stmts;
67 }
68 }
69
70 if (jp instanceof ConstructorExecutionJp) {
71 if (formal != null && formal.getType().isObject()) {
72 jp.showWarning(this, CONSTRUCTOR_EXECUTION_BINDING_CHANGE);
73 }
74 }
75
76 ReturnFixerWalker walker = new ReturnFixerWalker(getCompiler(), plan);
77 Stmts ret = walker.removeReturns(stmts);
78 return ret;
79 }
80
81
93 static class ReturnFixerWalker extends Walker {
94 AdvicePlan plan;
95 VarDec thisResultVar;
96 String label;
97
98
99 public ReturnFixerWalker(JavaCompiler compiler, AdvicePlan plan) {
100 super(compiler);
101 this.plan = plan;
102 }
103
104 public Stmts removeReturns(Stmts stmts) {
105 final AST ast = getAST();
106 Type resultType = plan.getJoinPoint().getResultType();
107
108 Expr thisResultExpr;
109 Stmt returnStmt;
110
111 if (resultType.isVoid()) {
112 thisResultVar = null;
113 thisResultExpr = ast.makeNull();
115 returnStmt = ast.makeReturn();
116 } else {
117 thisResultVar =
118 ast.makeVarDec(resultType, "_thisResult", resultType.getNullExpr());
119 thisResultExpr = ast.makeVar(thisResultVar);
120 returnStmt = ast.makeReturn(ast.makeVar(thisResultVar));
121 }
122
123 label = getWorld().genLabel();
124
125 Stmts ret = (Stmts)process(stmts);
126
127 Stmt body = ast.makeLabeled(label, ast.makeIf(ast.makeLiteral(true),
128 ret.getSingleStmt()));
129
130 ret = ast.makeStmts(
131 body,
132 plan.makeCall(thisResultExpr),
133 returnStmt);
134
135 if (!resultType.isVoid()) {
136 ret.add(0, thisResultVar);
137 }
138
139 return ret;
140 }
141
142 boolean seenVoidReturn = false;
143 boolean seenAnyReturns = false;
144 public Stmt wrapReturn(ReturnStmt returnStmt) {
145 final AST ast = this.getAST();
146
147 Expr returnExpr = returnStmt.getExpr();
148 if (returnExpr == null) {
149 return ast.makeBreak(label);
150 } else {
151 return ast.makeBlock(
152 ast.makeSet(thisResultVar, returnExpr),
153 ast.makeBreak(label));
154 }
155 }
156
157 public ASTObject process(ASTObject object) {
158 if (object instanceof TypeDec) return object;
160 if (object instanceof AnonymousMethodExpr) return object;
161
162 if (object instanceof ReturnStmt) {
163 return wrapReturn((ReturnStmt)object);
164 }
165
166 return super.process(object);
167 }
168 }
169
170
173 protected void setupFlowWalker(FlowCheckerPass w) {
174 if (getExtraFormal() != null)
175 w.setVars(w.getVars().addAssigned(getExtraFormal()));
176 super.setupFlowWalker(w);
177 }
178
179 protected FormalDec extraFormal;
181 public FormalDec getExtraFormal() { return extraFormal; }
182 public void setExtraFormal(FormalDec _extraFormal) {
183 if (_extraFormal != null) _extraFormal.setParent(this);
184 extraFormal = _extraFormal;
185 }
186
187 public AfterReturningAdviceDec(SourceLocation location, Modifiers _modifiers, Formals _formals, FormalDec _extraFormal, TypeDs __throws, Pcd _pcd, CodeBody _body) {
188 super(location, _modifiers, _formals, __throws, _pcd, _body);
189 setExtraFormal(_extraFormal);
190 }
191 protected AfterReturningAdviceDec(SourceLocation source) {
192 super(source);
193 }
194
195 public ASTObject copyWalk(CopyWalker walker) {
196 AfterReturningAdviceDec ret = new AfterReturningAdviceDec(getSourceLocation());
197 ret.preCopy(walker, this);
198 if (modifiers != null) ret.setModifiers( (Modifiers)walker.process(modifiers) );
199 if (formals != null) ret.setFormals( (Formals)walker.process(formals) );
200 if (extraFormal != null) ret.setExtraFormal( (FormalDec)walker.process(extraFormal) );
201 if (_throws != null) ret.setThrows( (TypeDs)walker.process(_throws) );
202 if (pcd != null) ret.setPcd( (Pcd)walker.process(pcd) );
203 if (body != null) ret.setBody( (CodeBody)walker.process(body) );
204 return ret;
205 }
206
207 public ASTObject getChildAt(int childIndex) {
208 switch(childIndex) {
209 case 0: return modifiers;
210 case 1: return formals;
211 case 2: return extraFormal;
212 case 3: return _throws;
213 case 4: return pcd;
214 case 5: return body;
215 default: return super.getChildAt(childIndex);
216 }
217 }
218 public String getChildNameAt(int childIndex) {
219 switch(childIndex) {
220 case 0: return "modifiers";
221 case 1: return "formals";
222 case 2: return "extraFormal";
223 case 3: return "throws";
224 case 4: return "pcd";
225 case 5: return "body";
226 default: return super.getChildNameAt(childIndex);
227 }
228 }
229 public void setChildAt(int childIndex, ASTObject child) {
230 switch(childIndex) {
231 case 0: setModifiers((Modifiers)child); return;
232 case 1: setFormals((Formals)child); return;
233 case 2: setExtraFormal((FormalDec)child); return;
234 case 3: setThrows((TypeDs)child); return;
235 case 4: setPcd((Pcd)child); return;
236 case 5: setBody((CodeBody)child); return;
237 default: super.setChildAt(childIndex, child); return;
238 }
239 }
240 public int getChildCount() {
241 return 6;
242 }
243
244 public String getDefaultDisplayName() {
245 return "AfterReturningAdviceDec()";
246 }
247
248 }
250 |
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