基于ArrayList实现的简易版ArrayQueue

Posted 2021-03-18 esrevinud

参考接口

public interface myQueue<T> {
    void offer(T element);
    T poll();
    T peek();
    Boolean isEmpty();
    Integer size();
    void clear();
}

实现代码

import java.util.ArrayList;

public class MyArrayQueue<T> implements myQueue<T> {

    private ArrayList<T> core;

    public MyArrayQueue() {
        this(10);
    }

    public MyArrayQueue(int capacity) {
        core = new ArrayList<>(capacity);
    }

    @Override
    public void offer(T element) {
        core.add(element);
    }

    @Override
    public T poll() {
        return core.remove(0);
    }

    @Override
    public T peek() {
        return core.get(0);
    }

    @Override
    public Boolean isEmpty() {
        return core.isEmpty();
    }

    @Override
    public Integer size() {
        return core.size();
    }

    @Override
    public void clear() {
        core.clear();
    }

    public static void main(String[] args) {
        MyArrayQueue<Integer> queue = new MyArrayQueue<>();
        for (int i = 0; i < 10; i ++) {
            queue.offer(i);
        }

        System.out.println(queue.peek());
        queue.poll();
        System.out.println(queue.peek());

    }
}