集合运算 - Java实现集合的交、并、差

package com.lfy.Set;

import java.util.HashSet;
import java.util.Set;

/**
 * 集合的交、并、差
 * @author lfy
 *
 */
public class CollectionOperation {
    public static void main(String[] args) {
        Set<Integer> result = new HashSet<Integer>();
        Set<Integer> set1 = new HashSet<Integer>() {
            private static final long serialVersionUID = 1L;
            {
                add(1);
                add(3);
                add(5);
            }};
        
        Set<Integer> set2 = new HashSet<Integer>(){
            private static final long serialVersionUID = 1L;
            {
                add(1);
                add(2);
                add(3);
            }};
        System.out.println("set1:"+set1);
        System.out.println("set2:"+set2);
        //交集
        result.clear();
        result.addAll(set1);
        result.retainAll(set2);
        System.out.println("交集:"+result);
        
        //差集
        result.clear();
        result.addAll(set1);
        result.removeAll(set2);
        System.out.println("差集:"+result);
        
        //并集
        result.clear();
        result.addAll(set1);
        result.addAll(set2);
        System.out.println("并集:"+result);

    }
}

set1:[1, 3, 5]
set2:[1, 2, 3]
交集:[1, 3]
差集:[5]
并集:[1, 2, 3, 5]