[java] ConcurrentHashMap iterator 사용법

java의 concurrentHashMap 사용법.

 

entrySet을 이용하여 key, value를 가져올 수 있다.

 

첫번째 사용법: entrySet과 for loop로 접근

import java.util.concurrent.ConcurrentHashMap;

public class ConcurrentHashMapTest {

	private final ConcurrentHashMap <String, String> map = new ConcurrentHashMap<String, String>();
    
	public void test() {
		map.put("name", "hong");
		map.put("param", "test");

		for(ConcurrentHashMap.Entry<String, String> entry : map.entrySet()) {
			String key = entry.getKey();
			String value = entry.getValue();
		}
	}
}

 

두번째 사용법: iterator로 접근

import java.util.concurrent.ConcurrentHashMap;
import java.util.Iterator;
import java.util.Set;

public class ConcurrentHashMapTest {

	private final ConcurrentHashMap <String, String> map = new ConcurrentHashMap<String, String>();
    
	public void test() {
		map.put("name", "hong");
		map.put("param", "test");

		Set<ConcurrentHashMap.Entry<String, String>> entry = map.entrySet();
		Iterator<ConcurrentHashMap.Entry<String, String>> it = entry.iterator();
		while(it.hasNex()) {
			ConcurrentHashMap.Entry<String, String>> data = it.next();
			String key = data.getKey();
			String value = data.getValue();
		}
	}
}