JAVA 交集，差集，并集

package test;

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

public class Test {
	
	public static void main(String[] args) {
		Set result = new HashSet();
		Set set1 = new HashSet(){{
			add(1);
			add(3);
			add(5);
		}};
		
		Set set2 = new HashSet(){{
			add(1);
			add(2);
			add(3);
		}};
		
		result.clear();
		result.addAll(set1);
		result.retainAll(set2);
		System.out.println("交集："+result);
		
		result.clear();
		result.addAll(set1);
		result.removeAll(set2);
		System.out.println("差集："+result);
		
		result.clear();
		result.addAll(set1);
		result.addAll(set2);
		System.out.println("并集："+result);
		
	}

}