public boolean contains(Call call) {
        for (ListIterator<Call> i = iterator(); i.hasNext();) {
            Call current = i.next();
            if (current == call) {
                return true;
            }
        }
        return false;
    }
Returns whether this stack has this call (left)

@param call
           the call to check
@return true if the call is present, false otherwise
docproc/src/main/java/com/yahoo/docproc/CallStack.java