/**
* overrides the visitor to initialize and tear down the opcode stack
*
* @param classContext the context object of the currently parsed class
*/
@Override
public void visitClassContext(ClassContext classContext) {
try {
String clsName = classContext.getJavaClass().getClassName();
isInnerClass = clsName.contains("$");
clsSignature = SignatureUtils.classToSignature(clsName);
stack = new OpcodeStack();
localSpecialObjects = new HashMap<>();
fieldSpecialObjects = new HashMap<>();
super.visitClassContext(classContext);
if (!isInnerClass && !fieldSpecialObjects.isEmpty()) {
for (Map.Entry<String, String> entry : fieldSpecialObjects.entrySet()) {
String fieldName = entry.getKey();
String signature = entry.getValue();
bugReporter.reportBug(
makeFieldBugInstance().addClass(this).addField(clsName, fieldName, signature, false));
}
}
} finally {
stack = null;
localSpecialObjects = null;
fieldSpecialObjects = null;
}
}
/**
* Checks to see if any of the locals or fields that we are tracking are passed into another
* method. If they are, we clear out our tracking of them, because we can't easily track their
* progress into the method.
*
* <p>This can be overridden to check for exceptions to this rule, for example, being logged to
* the console not counting.
*/
protected void processMethodParms() {
String sig = getSigConstantOperand();
int numParms = SignatureUtils.getNumParameters(sig);
if ((numParms > 0) && (stack.getStackDepth() >= numParms)) {
for (int i = 0; i < numParms; i++) {
clearUserValue(stack.getStackItem(i));
}
}
}
private void sawInvokeInterfaceVirtual() {
String sig = getSigConstantOperand();
int numParms = SignatureUtils.getNumParameters(sig);
if (stack.getStackDepth() > numParms) {
OpcodeStack.Item item = stack.getStackItem(numParms);
Object uo = item.getUserValue();
if (uo != null) {
String name = getNameConstantOperand();
if (isMethodThatShouldBeCalled(name)) {
clearUserValue(item);
} else if (!"clone".equals(name)) {
if ((!Values.SIG_VOID.equals(SignatureUtils.getReturnSignature(sig))) && !nextOpIsPop()) {
clearUserValue(item);
}
}
}
}
processMethodParms();
}
@Override
public void visitField(Field obj) {
if (!isInnerClass && obj.isPrivate() && !obj.isSynthetic()) {
String sig = obj.getSignature();
if (sig.startsWith(Values.SIG_QUALIFIED_CLASS_PREFIX)) {
String type = SignatureUtils.stripSignature(sig);
if (doesObjectNeedToBeWatched(type)) {
fieldSpecialObjects.put(obj.getName(), obj.getSignature());
}
}
}
}