public void scan(Callback callback) {
public void scan(Callback callback) throws CFGBuilderException, DataflowAnalysisException {
	public void scan(Callback callback) {		Iterator<BasicBlock> bbIter = cfg.blockIterator();		while (bbIter.hasNext()) {			BasicBlock basicBlock = bbIter.next();			Iterator<InstructionHandle> insIter = basicBlock.instructionIterator();			while (insIter.hasNext()) {				InstructionHandle handle = insIter.next();				callback.visitLocation(new Location(handle, basicBlock));			}		}	}