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1
24
25 package org.aspectj.compiler.base;
26
27 import org.aspectj.compiler.base.ast.*;
28
29
30 import java.util.*;
31
32
33 public class CanThrowWalker extends Walker {
34 Stack canThrow = null;
35
36 public static void checkThrows(CodeDec codeDec) {
37 if (codeDec.isSoftThrowable()) return ;
38
39 CanThrowWalker walker = new CanThrowWalker(codeDec);
40 walker.canThrow.push(makeThrowableSet(codeDec.getThrows()));
41
42 if (codeDec instanceof InitializerDec && !codeDec.isStatic()) {
43 TypeDec inTypeDec = codeDec.getBytecodeTypeDec();
44 if (inTypeDec.isAnonymous()) {
45 Set set = new HashSet();
46 walker.collectBadThrows(set);
47 walker.process(codeDec);
48 inTypeDec.getSoleConstructorDec().addThrows(set);
50 } else {
51 Set set = null;
52 for (Iterator i = inTypeDec.getNameType().getConstructors().iterator(); i.hasNext(); ) {
53 Constructor c = (Constructor)i.next();
54 if (set == null) {
55 set = makeThrowableSet(c.getThrows());
56 } else {
57 set = Type.intersect(set, makeThrowableSet(c.getThrows()));
58 }
59 }
60 codeDec.addThrows(set);
62 walker.canThrow.push(makeThrowableSet(codeDec.getThrows()));
63 walker.process(codeDec);
64 }
65 } else {
66 walker.process(codeDec);
67 }
68 }
69
70
71 private Set badThrows = null;
72
73 private CanThrowWalker(CodeDec codeDec) {
74 super(codeDec.getCompiler());
75 canThrow = new Stack();
76 }
77
78 void collectBadThrows(Set set) {
79 badThrows = set;
80 }
81
82
83 static Set makeThrowableSet(TypeDs _throws) {
84 if (_throws == null) return Collections.EMPTY_SET;
85
86 Set ret = new HashSet();
87
88 final int N = _throws.size();
89 for(int i=0; i<N; i++) {
90 Type exceptionType = _throws.get(i).getType();
91 ret.add(exceptionType);
92 }
93 return ret;
94 }
95
96 Collection makeThrowableSet(CatchClauses catchClauses) {
97 if (catchClauses == null) return Collections.EMPTY_SET;
98
99 Collection ret = new HashSet();
100
101 final int N = catchClauses.size();
102 for(int i=0; i<N; i++) {
103 Type exceptionType = catchClauses.get(i).getFormal().getType();
104 ret.add(exceptionType);
105 }
106 return ret;
107 }
108
109
110 boolean checkLegalThrow(ASTObject where, Type throwType) {
111 if (throwType.isUncheckedThrowable()) return true;
112
113 for (Iterator i = canThrow.iterator(); i.hasNext(); ) {
114 if (Type.hasMatchingType((Collection)i.next(), throwType)) {
115 return true;
116 }
117 }
118
119 if (badThrows != null) {
120 badThrows.add(throwType);
121 return true;
122 } else {
123 where.showError("unreported exception " + throwType.getString() +
124 "; must be caught or declared to be thrown");
125 return false;
126 }
127 }
128
129
130 void checkLegalThrows(ASTObject where, TypeDs throwTypeDs) {
131 if (throwTypeDs == null) return;
132
133 for (int i = 0; i < throwTypeDs.size(); i++) {
134 if (!checkLegalThrow(where, throwTypeDs.get(i).getType())) return;
135 }
136 }
137
138 public ASTObject process(ASTObject node) {
139 if (node instanceof TryCatchStmt) {
140 TryCatchStmt tryStmt = (TryCatchStmt)node;
141 canThrow.push(makeThrowableSet(tryStmt.getCatches()));
142 super.process(tryStmt.getBody());
143 canThrow.pop();
144 super.process(tryStmt.getCatches());
145 return node;
146 }
147
148 if (node instanceof ThrowStmt) {
149 ThrowStmt throwStmt = (ThrowStmt)node;
150 checkLegalThrow(throwStmt, throwStmt.getExpr().getType());
151 } else if (node instanceof CallExpr) {
152 CallExpr callExpr = (CallExpr)node;
153 if (callExpr.isSoftThrowable()) return super.process(node);
154 if (callExpr.getId().equals("aspectOf")) {
155 return super.process(node);
156 }
157
158 Method method = callExpr.getMethod();
159
160 if (method == null) {
161 return super.process(node);
163 }
164 checkLegalThrows(callExpr, method.getThrows());
165 } else if (node instanceof NewInstanceExpr) {
166 NewInstanceExpr newExpr = (NewInstanceExpr)node;
167 if (newExpr.isSoftThrowable()) return super.process(node);
168
169 Constructor init = newExpr.getConstructor();
170 checkLegalThrows(newExpr, init.getThrows());
171 } else if (node instanceof ConstructorCallExpr) {
172 ConstructorCallExpr newExpr = (ConstructorCallExpr)node;
173
175 Constructor init = newExpr.getConstructor();
176 checkLegalThrows(newExpr, init.getThrows());
177
178 }
179 if (node instanceof TypeDec) return node;
180 return super.process(node);
181 }
182 }
183
184 |
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