java獲取隨機不重復的數得值

假如我有一個數組： 

 

ArrayList<Integer> mArrayList = new ArrayList<Integer>();
    	mArrayList.add(0);
    	mArrayList.add(1);
    	mArrayList.add(2);
    	mArrayList.add(3);

我需要從中隨機抽取2個數  不能重復抽取，我就會用這個方法

 

 

 public void getValue(ArrayList<Integer> mArrayList){
    	Random mRandom = new Random();
    	int a = mRandom.nextInt(mArrayList.size());
    	
    	int value = mArrayList.get(a);
    	System.out.println(value + "");
    	mArrayList.remove(a);
    }

原理就是每抽取一次就刪除已經抽取出來的值，這樣獲取到的值就不會重復了

 

完整代碼：

 

package com.xiaoqiu.test;

import java.util.ArrayList;
import java.util.Random;

public class Test {
    public static void main(String[] args) {
    	ArrayList<Integer> mArrayList = new ArrayList<Integer>();
    	mArrayList.add(0);
    	mArrayList.add(1);
    	mArrayList.add(2);
    	mArrayList.add(3);
    	
    	Test mTest = new Test();
    	mTest.getValue(mArrayList);
    	mTest.getValue(mArrayList);
    }
    
    public void getValue(ArrayList<Integer> mArrayList){
    	Random mRandom = new Random();
    	int a = mRandom.nextInt(mArrayList.size());
    	
    	int value = mArrayList.get(a);
    	System.out.println(value + "");
    	mArrayList.remove(a);
    }
}

測試結果：

 

 

3

2

 

3

0

 

2

3