operator.java

class BaseOperator<T> implements IOperator<T> {

    public T operate(T x, T y) {}

    public boolean apply (Stack<T> stack) {
	try {
	    T x = stack.pop();
	    T y = stack.pop();
	} catch (EmptyStackException e) {
	    System.out.println("Stack has to few arguments, you cant operate on it.");
	    return false;
	}

	stack.push(operate(x,y));
	return true;
    }
}