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Map迭代模式与运行结果

发布时间: 2012-11-17 11:14:15 作者: rapoo

Map迭代方式与运行结果
package cn.com.ambow.spring.aop5;

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

public class MapTest {

/**
* Map迭代
* @param args
*/
public static void main(String[] args) {

Map map = new HashMap();

map.put(1, "one");
map.put(2, "two");
map.put(3, "three");
map.put(4, "four");

System.out.println("00000000"+map.get(2));
//第一种
Iterator it = map.entrySet().iterator();
while(it.hasNext()){

Map.Entry entry = (Entry) it.next();

Object key = entry.getKey();
Object val = entry.getValue();

System.out.println("entry***"+entry);
System.out.println("key是"+key);
System.out.println("val是"+val);
}
System.out.println("*******************");
//第二种 根据key取出的是value
for (Object key : map.keySet()) {

map.get(key);
System.out.println(key);
System.out.println(map.get(key));

}
System.out.println("&&&&&&&&&&&&&&&&&&");
//第三种map.get(key)取出的是value
Iterator its = map.keySet().iterator();

while(its.hasNext()){
Object key = its.next();
Object val = map.get(key);

System.out.println(key);
System.out.println(val);
}

}


/*//运行结果
00000000two
entry***1=one
key是1
val是one
entry***2=two
key是2
val是two
entry***3=three
key是3
val是three
entry***4=four
key是4
val是four
*******************
1
one
2
two
3
three
4
four
&&&&&&&&&&&&&&&&&&
1
one
2
two
3
three
4
four*/

}

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