最高效的遍歷map的每個entry的方法如下:
for (Map.Entry entry : map.entrySet()){
int key = (int) entry.getKey();
int value = (int) entry.getValue();}
也可以使用iterator,特別是JDK 1.5之前。
Iterator itr = map.entrySet().iterator();while(itr.hasNext()){
Map.Entry entry = itr.next();
int key = (int) entry.getKey();
int value = (int) entry.getValue();}
Eg:
packagecom.zhiwenwu.map;
/*
* output
* 100 10
* 101 10
* 2017-11-09
* 寢室
*
*/
importjava.util.HashMap;
importjava.util.Map;
import javax.swing.text.html.HTMLDocument.Iterator;
public class D_Map {
public static void main(String[] args) {
// TODO Auto-generated method stub
HashMap<Integer,Integer> hp = new HashMap<>();
hp.put(100, 10);
hp.put(101,10);
for(Map.Entry en : hp.entrySet()){
System.out.print(en.getKey()+" "+en.getValue());
System.out.println();
}
}
}