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1
19
20 package edu.umd.cs.findbugs.detect;
21
22
23 import edu.umd.cs.findbugs.*;
24 import edu.umd.cs.findbugs.ba.*;
25 import edu.umd.cs.findbugs.ba.vna.*;
26
27 import java.util.*;
28 import org.apache.bcel.Constants;
29 import org.apache.bcel.classfile.*;
30 import org.apache.bcel.generic.*;
31
32 public final class FindMismatchedWaitOrNotify implements Detector, StatelessDetector {
33 private BugReporter bugReporter;
34
35 public FindMismatchedWaitOrNotify(BugReporter bugReporter) {
36 this.bugReporter = bugReporter;
37 }
38
39 @Override 
40 public Object clone() {
41 try {
42 return super.clone();
43 } catch (CloneNotSupportedException e) {
44 throw new AssertionError (e);
45 }
46 }
47
48 public void visitClassContext(ClassContext classContext) {
49 JavaClass jclass = classContext.getJavaClass();
50
51 Method[] methodList = jclass.getMethods();
52 for (Method method : methodList) {
53 MethodGen methodGen = classContext.getMethodGen(method);
54 if (methodGen == null)
55 continue;
56
57 BitSet bytecodeSet = classContext.getBytecodeSet(method);
60 if (bytecodeSet == null) continue;
61 if (!(bytecodeSet.get(Constants.MONITORENTER) && bytecodeSet.get(Constants.INVOKEVIRTUAL)))
62 continue;
63
64 try {
65 analyzeMethod(classContext, method);
66 } catch (DataflowAnalysisException e) {
67 bugReporter.logError("FindMismatchedWaitOrNotify: caught exception", e);
68 } catch (CFGBuilderException e) {
69 bugReporter.logError("FindMismatchedWaitOrNotify: caught exception", e);
70 }
71 }
72 }
73
74 private void analyzeMethod(ClassContext classContext, Method method)
75 throws CFGBuilderException, DataflowAnalysisException {
76
77 MethodGen methodGen = classContext.getMethodGen(method);
78 if (methodGen == null) return;
79 ConstantPoolGen cpg = methodGen.getConstantPool();
80 CFG cfg = classContext.getCFG(method);
81 ValueNumberDataflow vnaDataflow = classContext.getValueNumberDataflow(method);
82 LockDataflow dataflow = classContext.getLockDataflow(method);
83
84 for (Iterator<Location> i = cfg.locationIterator(); i.hasNext();) {
85 Location location = i.next();
86
87 InstructionHandle handle = location.getHandle();
88
89 Instruction ins = handle.getInstruction();
90 if (!(ins instanceof INVOKEVIRTUAL))
91 continue;
92 INVOKEVIRTUAL inv = (INVOKEVIRTUAL) ins;
93
94 String methodName = inv.getName(cpg);
95 String methodSig = inv.getSignature(cpg);
96
97 if (Hierarchy.isMonitorWait(methodName, methodSig)
98 || Hierarchy.isMonitorNotify(methodName, methodSig)) {
99 int numConsumed = inv.consumeStack(cpg);
100 if (numConsumed == Constants.UNPREDICTABLE)
101 throw new DataflowAnalysisException("Unpredictable stack consumption", methodGen, handle);
102
103 ValueNumberFrame frame = vnaDataflow.getFactAtLocation(location);
104 if (!frame.isValid())
105 continue;
107 if (frame.getStackDepth() - numConsumed < 0)
108 throw new DataflowAnalysisException("Stack underflow", methodGen, handle);
109 ValueNumber ref = frame.getValue(frame.getNumSlots() - numConsumed);
110 LockSet lockSet = dataflow.getFactAtLocation(location);
111 int lockCount = lockSet.getLockCount(ref.getNumber());
112
113 if (lockCount == 0) {
114 Collection<ValueNumber> lockedValueNumbers = lockSet.getLockedValueNumbers(frame);
115 boolean foundMatch = false;
116 for(ValueNumber v : lockedValueNumbers)
117 if (frame.fuzzyMatch(ref, v)){
118 foundMatch = true;
119 break;
120 }
121
122 if (!foundMatch) {
123
124 String type = methodName.equals("wait")
125 ? "MWN_MISMATCHED_WAIT"
126 : "MWN_MISMATCHED_NOTIFY";
127 String sourceFile = classContext.getJavaClass().getSourceFileName();
128 int priority = method.isPublic() ? NORMAL_PRIORITY : LOW_PRIORITY;
131
132 bugReporter.reportBug(new BugInstance(this, type, priority)
133 .addClassAndMethod(methodGen, sourceFile)
134 .addSourceLine(classContext, methodGen, sourceFile, handle));
135 }
136 }
137 }
138 }
139 }
140
141 public void report() {
142 }
143 }
144
145 |
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