面试必备-Map集合遍历

Map集合遍历

package test;

import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
import java.util.Map.Entry;

public class TestMap {
	public static void main(String[] args){
		Map<String,String> map = new HashMap<>();
		map.put("zhangsan", "333");
		map.put("lisi", "444");
		map.put("wangwu", "555");
		map.put("liuliu", "666");
		
		
		//Map遍历方法一：通过Map.entrySet遍历key和value  (推荐使用)
		for (Map.Entry<String, String> m : map.entrySet()) {
			System.out.println("key:" + m.getKey() + " value:" + m.getValue());
		}
		
		
		//Map遍历方法二：通过迭代器遍历
		Iterator<Entry<String, String>> it = map.entrySet().iterator();
        while(it.hasNext()){
             Entry<String, String> entry = it.next();
             System.out.println("key:"+entry.getKey()+"  key:"+entry.getValue());
        }
        
        
        //Map遍历方法三：通过Map.keySet()遍历key和value
        for(String key:map.keySet()){
            String value = map.get(key).toString();//
            System.out.println("key:"+key+" vlaue:"+value);
        }
        
        
        //Map遍历方法四：通过Map.values()遍历所有的value，但不能遍历key
        for(String m:map.values()){
            System.out.println(m);
        }
        
	}
}

本文地址：https://blog.csdn.net/weixin_44231137/article/details/109637112