Java集合框架学习(十) LinkedHashMap详解
LinkedHashMap介绍
1.Key和Value都允许null;
2.维护key的插入顺序;
3.非线程安全;
4.Key重复会覆盖、Value允许重复。
类定义
public class LinkedHashMap<K,V>
extends HashMap<K,V>implements Map<K,V>
例子介绍
package com.dylan.collection;
import java.util.Iterator;
import java.util.LinkedHashMap;
import java.util.Map;
import java.util.Set;
/**
* @author xusucheng
* @create 2018-02-03
**/
public class LinkedHashMapExample {
public static void main(String args[]) {
// HashMap Declaration
LinkedHashMap<Integer, String> lhmap =
new LinkedHashMap<Integer, String>();
//Adding elements to LinkedHashMap
lhmap.put(22, "Abey");
lhmap.put(33, "Dawn");
lhmap.put(1, "Sherry");
lhmap.put(2, "Karon");
lhmap.put(100, "Jim");
// Generating a Set of entries
Set set = lhmap.entrySet();
// Displaying elements of LinkedHashMap
Iterator iterator = set.iterator();
while(iterator.hasNext()) {
Map.Entry me = (Map.Entry)iterator.next();
System.out.print("Key is: "+ me.getKey() +
"& Value is: "+me.getValue()+"\n");
}
}
}