[java] Map을 로그에 출력하는 방법

import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
 
public class MapIterationSample {
 
    public static void main(String[] args) {
        
        HashMap<String, String> hashMap  = new HashMap<String, String>();
 
        hashMap.put("test3", "name5");
        hashMap.put("test4", "name2");
        hashMap.put("test5", "name1");
        hashMap.put("test1", "name3");
        hashMap.put("test2", "name4");
 
 
        System.out.println("=================Type1=================");
 
        Iterator<String> mapIter = hashMap.keySet().iterator();
 
        while(mapIter.hasNext()){
 
            String key = mapIter.next();
            String value = hashMap.get( key );
 
            System.out.println(key+" : "+value);
 
        }
 
        System.out.println("=================Type2=================");
 
        for(Map.Entry<String, String> elem : hashMap.entrySet()){
 
            String key = elem.getKey();
            String value = elem.getValue();
 
            System.out.println(key+" : "+value);
 
        }
 
        System.out.println("=================Type2=================");
 
        for(String key : hashMap.keySet()){
 
            String value = hashMap.get(key);
 
            System.out.println(key+" : "+value);
 
        }
 
 
    }
 
}

 

 

 

java8부터는 stream의 forEach를 사용.

 

map.forEach((key, value) -> { logger.debug(key + " : " + value); });​