Create A Program Called MyStack

We have to create a program called MyStack.In Push: Add one element at the end of the buffer.In Pull: Remove one element from the end of the buffer. In isEmpty: Should check if the list is empty or not and return the result as a boolean variable.

I am totally confused, I wrote the buffer and the array, but how do i add an remove element from the buffer?How do i add an element? What Statement do i Use?

Java Code: public class MyStack<T> implements Stack<T> {
private final T[] ringbuffer;
int index = 0;
int last;

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