Stack/src/ArrayStack.java

public class ArrayStack<E> implements Stack<E> {
    Array<E> array;
    public ArrayStack(int capacity){
        array = new Array<>(capacity);
    }
    public ArrayStack(){
        array = new Array<>();
    }
    @Override
    public int getSize(){
        return array.getSize();
    }

    @Override
    public boolean isEmpty(){
        return array.isEmpty();
    }

    public int getCapacity(){
        return array.getCapacity();
    }

    @Override
    public void push(E e){
        array.addLast(e);
    }

    @Override
    public E pop(){
        return array.removeLast();
    }

    @Override
    public E peek(){
        return array.get(array.getSize()-1);
    }

    @Override
    public String toString(){
        StringBuilder stringBuilder = new StringBuilder();
        stringBuilder.append("Stack:[");
        for(int i=0;i<array.getSize();i++){
            stringBuilder.append(array.get(i));
            if(i<array.getSize()-1)
                stringBuilder.append(",");
            else
                stringBuilder.append("]");
        }
        return stringBuilder.toString();
    }
}