LinkedHashMap和HashMap的比较使用

import java.util.HashMap;

import java.util.Iterator;

import java.util.LinkedHashMap;

import java.util.Map;

public class TestLinkedHashMap {

public static void main(String args[])

{

System.out.println("*************************LinkedHashMap*************");

Map<Integer,String> map = new LinkedHashMap<Integer,String>();

map.put(6, "apple");

map.put(3, "banana");

map.put(2,"pear");

for (Iterator it = map.keySet().iterator();it.hasNext();)

{

Object key = it.next();

System.out.println( key+"="+ map.get(key));

}

System.out.println("*************************HashMap*************");

Map<Integer,String> map1 = new HashMap<Integer,String>();

map1.put(6, "apple");

map1.put(3, "banana");

map1.put(2,"pear");

for (Iterator it = map1.keySet().iterator();it.hasNext();)

{

Object key = it.next();

System.out.println( key+"="+ map1.get(key));

}

}

}

运行结果如下:

*************************LinkedHashMap*************

6=apple

3=banana

2=pear

*************************HashMap**************************

2=pear

6=apple

3=banana

分析:LinkedHashmap 的特点是put进去的对象位置未发生变化,而HashMap会发生变化.