java day8 Map集合系列

1、可变参数

    public static void main(String[] args) {
        text(); //0
        text(1,2,3);//3 1 2 3
        text(new int[]{20,30,40,50});//4 20,30,40,50

    }
    public static void text(int...nums){
        System.out.println(nums.length);
        for (int i = 0; i < nums.length; i++) {
            System.out.print(nums[i]+" ");
        }
        System.out.println();
    }
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2、Collections

操作集合的工具类
常用方法：

  List<Integer> list=new ArrayList<>();
        //为集合加入一批数据
        Collections.addAll(list,1,2,5,4);
        System.out.println(list);//[1, 2, 5, 4]
        //打乱集合中的数据
        Collections.shuffle(list);
        System.out.println(list);//[4, 2, 5, 1]
        //排序
        Collections.sort(list);
        System.out.println(list);//[1, 2, 4, 5]
        //如果是为 一个类排序 则需要该类继承Comparable<> 并重写其中的方法
        //或者使用 sort
        Collections.sort(list, new Comparator<Integer>() {
            @Override
            public int compare(Integer o1, Integer o2) {
                return o1-o2;
            }
        });
        System.out.println(list);//[1, 2, 4, 5]
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3、斗地主游戏综合案例

Card类：

package com.cky.Collecting;

public class Card {
    private String number; //牌数字
    private String color; //排颜色
    private int size; //牌大小

    public Card(String number, String color, int size) {
        this.number = number;
        this.color = color;
        this.size = size;
    }

    public Card() {
    }

    @Override
    public String toString() {
        return color+number;
    }

    public String getNumber() {
        return number;
    }

    public void setNumber(String number) {
        this.number = number;
    }

    public String getColor() {
        return color;
    }

    public void setColor(String color) {
        this.color = color;
    }

    public int getSize() {
        return size;
    }

    public void setSize(int size) {
        this.size = size;
    }
}

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Room类：

package com.cky.Collecting;

import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
import java.util.List;

public class Room {
    //必须要有一副牌
    public List<Card> Allcards=new ArrayList<>();

    public Room(){
        String[] numbers={String[] numbers={"3","4","5","6","7","8","9","10","J","Q","K","A","2"};};
        String[] colors={"♦","❤","
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