Java如何判断Set是否有交集呢?

Set是否有交集的判断方法

使用retainAll方法
    即可判断set是否有交集

package com.java265.dto;
 
import org.apache.commons.lang3.StringUtils;
import org.springframework.util.CollectionUtils;
 
import java.util.Arrays;
import java.util.HashSet;
import java.util.Set;
 
/**
 * Description: 判断是否存在交集
 */
public class SetDemo {
 
    public static void main(String[] args) {
        String c5listName = "java265.com-1,java爱好者";
        String c5Config = "web开发,java,java265,java爱好者";
 
        String[] split1 = c5ListName.split(",");
        String[] split2 = c5Config.split(",");
 
        Set<String> set1 = new HashSet<>(Arrays.asList(split1));
        Set<String> set2 = new HashSet<>(Arrays.asList(split2));
 
        set1.retainAll(set2);
        
        System.out.println(set1);
        
        if (!CollectionUtils.isEmpty(set1)) {
            System.out.println("有交集");
        } else {
            System.out.println("无交集");
        }
    }
}
 

package com.java265.dto;
  
public class SetDemo2 {
 
    public static void main(String[] args) {
        String c5ListName = "java265.com-1,java爱好者";
        String c5Config = "web开发,java,java265,java爱好者";
 
        String[] split1 = c5ListName.split(",");
        String[] split2 = c5Config.split(",");
 
        System.out.println(isContainSet(split1, split2));
    }
 
    public static boolean isContainSet(String[] split1, String[] split2) {
        for (int i = 0; i < split1.length; i++) {
            for (int j = 0; j < split2.length; j++) {
                if (split1[i].equals(split2[j])) {
                    System.out.println("有交集" + j);
                    return true;
                }
            }
        }
        return false;
    }
}