栈的基本操作

首先声明几个要实现的方法

public interface Stack<E> {
    E pop();
    E peek();
    void push(E e);
    int getSize();
    boolean isEmpty();
}

紧接着结合动态数组进行包装

public class ArrayStack<E> implements Stack<E> {
    Array<E> array;
    public  ArrayStack(){
        array =new Array<E>();
    }

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

    @Override
    public int getSize() {
        return array.getSize();
    }

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

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



    @Override
    public E peek() {
        return array.getLast();
    }
    @Override
    public String toString(){
        StringBuilder ab=new StringBuilder();
        ab.append("Stack [");
        for (int i=0;i<array.getSize();i++){
                ab.append(array.get(i));
            if (i!=array.getSize()-1)
                ab.append(", ");
        }
        ab.append("] top ");
        return ab.toString();
    }

}