Java CFG类代码示例

import edu.umd.cs.findbugs.ba.CFG; //导入依赖的package包/类
/**
 * Check if the readObject is doing multiple external call beyond the basic readByte, readBoolean, etc..
 * @param m
 * @param classContext
 * @return
 * @throws CFGBuilderException
 * @throws DataflowAnalysisException
 */
private boolean hasCustomReadObject(Method m, ClassContext classContext,List<String> classesToIgnore)
        throws CFGBuilderException, DataflowAnalysisException {
    ConstantPoolGen cpg = classContext.getConstantPoolGen();
    CFG cfg = classContext.getCFG(m);
    int count = 0;
    for (Iterator<Location> i = cfg.locationIterator(); i.hasNext(); ) {
        Location location = i.next();
        Instruction inst = location.getHandle().getInstruction();
        //ByteCode.printOpCode(inst,cpg);
        if(inst instanceof InvokeInstruction) {
            InvokeInstruction invoke = (InvokeInstruction) inst;
            if (!READ_DESERIALIZATION_METHODS.contains(invoke.getMethodName(cpg))
                    && !classesToIgnore.contains(invoke.getClassName(cpg))) {
                count +=1;
            }
        }
    }
    return count > 3;
}
 

import edu.umd.cs.findbugs.ba.CFG; //导入依赖的package包/类
private void analyzeMethod(Method m, ClassContext classContext) throws CFGBuilderException, DataflowAnalysisException {
    MethodGen methodGen = classContext.getMethodGen(m);
    ConstantPoolGen cpg = classContext.getConstantPoolGen();
    CFG cfg = classContext.getCFG(m);

    if (methodGen == null || methodGen.getInstructionList() == null) {
        return; //No instruction .. nothing to do
    }
    for (Iterator<Location> i = cfg.locationIterator(); i.hasNext(); ) {
        Location location = i.next();
        Instruction inst = location.getHandle().getInstruction();
        if (inst instanceof InvokeInstruction) {
            InvokeInstruction invoke = (InvokeInstruction) inst;
            String methodName = invoke.getMethodName(cpg);
            if ("enableDefaultTyping".equals(methodName)) {
                JavaClass clz = classContext.getJavaClass();
                bugReporter.reportBug(new BugInstance(this, DESERIALIZATION_TYPE, HIGH_PRIORITY)
                        .addClass(clz)
                        .addMethod(clz, m)
                        .addCalledMethod(cpg, invoke)
                        .addSourceLine(classContext, m, location)
                );
            }
        }
    }
}
 

import edu.umd.cs.findbugs.ba.CFG; //导入依赖的package包/类
private void analyzeMethod(Method m, ClassContext classContext) throws CFGBuilderException, DataflowAnalysisException {

        ConstantPoolGen cpg = classContext.getConstantPoolGen();
        CFG cfg = classContext.getCFG(m);
        
        for (Iterator<Location> i = cfg.locationIterator(); i.hasNext(); ) {
            Location location = i.next();

            Instruction inst = location.getHandle().getInstruction();
            
            if (inst instanceof LDC) {
                LDC ldc = (LDC) inst;
                if (ldc != null) {
                    if("java.naming.security.authentication".equals(ldc.getValue(cpg)) &&
                       "none".equals(ByteCode.getConstantLDC(location.getHandle().getNext(), cpg, String.class))){
                        JavaClass clz = classContext.getJavaClass();
                        bugReporter.reportBug(new BugInstance(this, LDAP_ANONYMOUS, Priorities.LOW_PRIORITY) //
                        .addClass(clz)
                        .addMethod(clz, m)
                        .addSourceLine(classContext, m, location));
                        break;
                    }
                }
            }            
        }
    }
 

import edu.umd.cs.findbugs.ba.CFG; //导入依赖的package包/类
/**
 * Count stores, loads, and increments of local variables in method whose
 * CFG is given.
 * 
 * @param localStoreCount
 *            counts of local stores (indexed by local)
 * @param localLoadCount
 *            counts of local loads (indexed by local)
 * @param localIncrementCount
 *            counts of local increments (indexed by local)
 * @param cfg
 *            control flow graph (CFG) of method
 */
private void countLocalStoresLoadsAndIncrements(int[] localStoreCount, int[] localLoadCount, int[] localIncrementCount,
        CFG cfg) {
    for (Iterator<Location> i = cfg.locationIterator(); i.hasNext();) {
        Location location = i.next();

        if (location.getBasicBlock().isExceptionHandler())
            continue;

        boolean isStore = isStore(location);
        boolean isLoad = isLoad(location);
        if (!isStore && !isLoad)
            continue;

        IndexedInstruction ins = (IndexedInstruction) location.getHandle().getInstruction();
        int local = ins.getIndex();
        if (ins instanceof IINC) {
            localStoreCount[local]++;
            localLoadCount[local]++;
            localIncrementCount[local]++;
        } else if (isStore)
            localStoreCount[local]++;
        else
            localLoadCount[local]++;
    }
}
 

import edu.umd.cs.findbugs.ba.CFG; //导入依赖的package包/类
private void checkForConflictingValues(XMethod xMethod, CFG cfg,
        TypeQualifierValue typeQualifierValue, TypeQualifierValueSet forwardsFact, TypeQualifierValueSet backwardsFact,
        Location locationToReport, Location locationWhereDoomedValueIsObserved, ValueNumberFrame vnaFrame) throws CheckedAnalysisException {
    Set<ValueNumber> valueNumberSet = new HashSet<ValueNumber>();
    valueNumberSet.addAll(forwardsFact.getValueNumbers());
    valueNumberSet.addAll(backwardsFact.getValueNumbers());

    for (ValueNumber vn : valueNumberSet) {
        FlowValue forward = forwardsFact.getValue(vn);
        FlowValue backward = backwardsFact.getValue(vn);
        if (!FlowValue.valuesConflict(typeQualifierValue.isStrictQualifier() && !xMethod.isIdentity(), forward, backward))
            continue;

        if (DEBUG) {
            System.out.println("Check " + vn + ": forward=" + forward + ", backward=" + backward + " at " + checkLocation);
            forwardsFact.getValue(vn);
            backwardsFact.getValue(vn);
        }

        emitDataflowWarning(xMethod, typeQualifierValue, forwardsFact, backwardsFact, vn, forward, backward,
                locationToReport, locationWhereDoomedValueIsObserved, vnaFrame);

    }
}
 

import edu.umd.cs.findbugs.ba.CFG; //导入依赖的package包/类
private @CheckForNull
Location getPreviousLocation(CFG cfg, Location startLocation, boolean skipNops) {
    Location loc = startLocation;
    InstructionHandle prev = getPreviousInstruction(loc.getHandle(), skipNops);
    if (prev != null)
        return new Location(prev, loc.getBasicBlock());
    BasicBlock block = loc.getBasicBlock();
    while (true) {
        block = cfg.getPredecessorWithEdgeType(block, EdgeTypes.FALL_THROUGH_EDGE);
        if (block == null)
            return null;
        InstructionHandle lastInstruction = block.getLastInstruction();
        if (lastInstruction != null)
            return new Location(lastInstruction, block);
    }
}
 

import edu.umd.cs.findbugs.ba.CFG; //导入依赖的package包/类
private boolean isSafeValue(Location location, ConstantPoolGen cpg) throws CFGBuilderException {
    Instruction prevIns = location.getHandle().getInstruction();
    if (prevIns instanceof LDC || prevIns instanceof GETSTATIC)
        return true;
    if (prevIns instanceof InvokeInstruction) {
        String methodName = ((InvokeInstruction) prevIns).getMethodName(cpg);
        if (methodName.startsWith("to") && methodName.endsWith("String") && methodName.length() > 8)
            return true;
    }
    if (prevIns instanceof AALOAD) {
        CFG cfg = classContext.getCFG(method);

        Location prev = getPreviousLocation(cfg, location, true);
        if (prev != null) {
            Location prev2 = getPreviousLocation(cfg, prev, true);
            if (prev2 != null && prev2.getHandle().getInstruction() instanceof GETSTATIC) {
                GETSTATIC getStatic = (GETSTATIC) prev2.getHandle().getInstruction();
                if (getStatic.getSignature(cpg).equals("[Ljava/lang/String;"))
                    return true;
            }
        }
    }
    return false;
}
 

import edu.umd.cs.findbugs.ba.CFG; //导入依赖的package包/类
private InstructionHandle findThenFinish(CFG cfg, BasicBlock thenBB, int elsePos) {
    InstructionHandle inst = thenBB.getFirstInstruction();
    while (inst == null) {
        Iterator<Edge> ie = cfg.outgoingEdgeIterator(thenBB);
        while (ie.hasNext()) {
            Edge e = ie.next();
            if (e.getType() == EdgeTypes.FALL_THROUGH_EDGE) {
                thenBB = e.getTarget();
                break;
            }
        }
        inst = thenBB.getFirstInstruction();
    }

    InstructionHandle lastIns = inst;
    while (inst.getPosition() < elsePos) {
        lastIns = inst;
        inst = inst.getNext();
    }

    return lastIns;
}
 

import edu.umd.cs.findbugs.ba.CFG; //导入依赖的package包/类
/**
 * @param propertySet
 * @param pc
 * @param isConsistent
 * @return
 */
public boolean isDuplicated(WarningPropertySet<WarningProperty> propertySet, int pc, boolean isConsistent) {
    boolean duplicated = false;
    if (!isConsistent) {
        if (propertySet.containsProperty(NullDerefProperty.DEREFS_ARE_CLONED))
            duplicated = true;

        else
            try {
                CFG cfg = classContext.getCFG(method);
                if (cfg.getLocationsContainingInstructionWithOffset(pc).size() > 1) {
                    propertySet.addProperty(NullDerefProperty.DEREFS_ARE_INLINED_FINALLY_BLOCKS);
                    duplicated = true;
                }
            } catch (CFGBuilderException e) {
                AnalysisContext.logError("Error while analyzing " + classContext.getFullyQualifiedMethodName(method), e);
            }
    }
    return duplicated;
}
 

import edu.umd.cs.findbugs.ba.CFG; //导入依赖的package包/类
private ResourceCollection<Resource> buildResourceCollection(ClassContext classContext, Method method,
        ResourceTrackerType resourceTracker) throws CFGBuilderException, DataflowAnalysisException {

    ResourceCollection<Resource> resourceCollection = new ResourceCollection<Resource>();

    CFG cfg = classContext.getCFG(method);
    ConstantPoolGen cpg = classContext.getConstantPoolGen();

    for (Iterator<Location> i = cfg.locationIterator(); i.hasNext();) {
        Location location = i.next();
        Resource resource = resourceTracker.isResourceCreation(location.getBasicBlock(), location.getHandle(), cpg);
        if (resource != null)
            resourceCollection.addCreatedResource(location, resource);
    }

    return resourceCollection;
}
 

import edu.umd.cs.findbugs.ba.CFG; //导入依赖的package包/类
public LiveLocalStoreDataflow analyze(IAnalysisCache analysisCache, MethodDescriptor descriptor)
        throws CheckedAnalysisException {
    MethodGen methodGen = getMethodGen(analysisCache, descriptor);
    if (methodGen == null) {
        return null;
    }
    CFG cfg = getCFG(analysisCache, descriptor);

    ReverseDepthFirstSearch rdfs = getReverseDepthFirstSearch(analysisCache, descriptor);

    LiveLocalStoreAnalysis analysis = new LiveLocalStoreAnalysis(methodGen, rdfs, getDepthFirstSearch(analysisCache,
            descriptor));
    LiveLocalStoreDataflow dataflow = new LiveLocalStoreDataflow(cfg, analysis);

    dataflow.execute();
    if (ClassContext.DUMP_DATAFLOW_ANALYSIS) {
        ClassContext.dumpLiveLocalStoreDataflow(descriptor, cfg, dataflow);

    }
    return dataflow;
}
 

import edu.umd.cs.findbugs.ba.CFG; //导入依赖的package包/类
public void visitClass(ClassDescriptor classDescriptor) throws CheckedAnalysisException {
    IAnalysisCache analysisCache = Global.getAnalysisCache();

    JavaClass jclass = analysisCache.getClassAnalysis(JavaClass.class, classDescriptor);
    classContext = analysisCache.getClassAnalysis(ClassContext.class, classDescriptor);

    for (Method m : classContext.getMethodsInCallOrder()) {
        if (m.getCode() == null) {
            continue;
        }
        method = m;

        MethodDescriptor methodDescriptor = BCELUtil.getMethodDescriptor(jclass, method);

        // Try to get MethodGen. If we can't get one,
        // then this method should be skipped.
        MethodGen methodGen = analysisCache.getMethodAnalysis(MethodGen.class, methodDescriptor);
        if (methodGen == null) {
            continue;
        }

        CFG cfg = analysisCache.getMethodAnalysis(CFG.class, methodDescriptor);
        visitMethodCFG(methodDescriptor, cfg);
    }
}
 

import edu.umd.cs.findbugs.ba.CFG; //导入依赖的package包/类
public IsNullValueAnalysis(MethodDescriptor descriptor, MethodGen methodGen, CFG cfg, ValueNumberDataflow vnaDataflow,
        TypeDataflow typeDataflow, DepthFirstSearch dfs, AssertionMethods assertionMethods) {
    super(dfs);

    this.trackValueNumbers = AnalysisContext.currentAnalysisContext().getBoolProperty(
            AnalysisFeatures.TRACK_VALUE_NUMBERS_IN_NULL_POINTER_ANALYSIS);

    this.methodGen = methodGen;
    this.visitor = new IsNullValueFrameModelingVisitor(methodGen.getConstantPool(), assertionMethods, vnaDataflow,
            typeDataflow, trackValueNumbers);
    this.vnaDataflow = vnaDataflow;
    this.cfg = cfg;
    this.locationWhereValueBecomesNullSet = new HashSet<LocationWhereValueBecomesNull>();
    this.pointerEqualityCheck = getForPointerEqualityCheck(cfg, vnaDataflow);

    if (DEBUG) {
        System.out.println("IsNullValueAnalysis for " + methodGen.getClassName() + "." + methodGen.getName() + " : "
                + methodGen.getSignature());
    }
}
 

import edu.umd.cs.findbugs.ba.CFG; //导入依赖的package包/类
private static Map<InstructionHandle, Call> buildCallMap(CFG cfg, ConstantPoolGen cpg) {
    Map<InstructionHandle, Call> callMap = new HashMap<InstructionHandle, Call>();

    for (Iterator<Location> i = cfg.locationIterator(); i.hasNext();) {
        InstructionHandle handle = i.next().getHandle();
        Instruction ins = handle.getInstruction();

        if (ins instanceof InvokeInstruction) {
            InvokeInstruction inv = (InvokeInstruction) ins;
            Call call = new Call(inv.getClassName(cpg), inv.getName(cpg), inv.getSignature(cpg));
            callMap.put(handle, call);
        }
    }

    return callMap;
}
 

import edu.umd.cs.findbugs.ba.CFG; //导入依赖的package包/类
/**
 * Constructor.
 * 
 * @param method
 *            TODO
 * @param methodGen
 *            the MethodGen whose CFG we'll be analyzing
 * @param cfg
 *            the control flow graph
 * @param dfs
 *            DepthFirstSearch of the method
 * @param typeMerger
 *            object to merge types
 * @param visitor
 *            a TypeFrameModelingVisitor to use to model the effect of
 *            instructions
 * @param lookupFailureCallback
 *            lookup failure callback
 * @param exceptionSetFactory
 *            factory for creating ExceptionSet objects
 */
public TypeAnalysis(Method method, MethodGen methodGen, CFG cfg, DepthFirstSearch dfs, TypeMerger typeMerger,
        TypeFrameModelingVisitor visitor, RepositoryLookupFailureCallback lookupFailureCallback,
        ExceptionSetFactory exceptionSetFactory) {
    super(dfs);
    this.method = method;
    Code code = method.getCode();
    if (code == null)
        throw new IllegalArgumentException(method.getName() + " has no code");
    for (Attribute a : code.getAttributes()) {
        if (a instanceof LocalVariableTypeTable) 
            visitor.setLocalTypeTable((LocalVariableTypeTable) a);
    }
    this.methodGen = methodGen;
    this.cfg = cfg;
    this.typeMerger = typeMerger;
    this.visitor = visitor;
    this.thrownExceptionSetMap = new HashMap<BasicBlock, CachedExceptionSet>();
    this.lookupFailureCallback = lookupFailureCallback;
    this.exceptionSetFactory = exceptionSetFactory;
    this.instanceOfCheckMap = new HashMap<BasicBlock, InstanceOfCheck>();
    if (DEBUG) {
        System.out.println("\n\nAnalyzing " + methodGen);
    }
}