Need Help with Data Structure Java

Methodologies. Suppose we have stacks named as st1, st2 1) enqueue(Object obj): a. pop all from st1-> st2 (if st1 is not empty), b. then push obj >st1 c. push all from st2 sti 2) dequeue() if st1 is empty, else pop st1. error (You can use an alternative strategy: a. for enqueue, push object obj to st1 first. b. For dequeue method, i. if both stacks is empty, then produce error. ii. If st2 is empty and st1 is not empty, pop all from st1-->st2 ii. Pop the element from st2 and return it