Map之Iterator

package smy.iterator;

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

public class TestMap {
    public static void main(String[] args) {
        Map map= new HashMap();
        map.put("flower","花");
        map.put("grass","草");
        map.put("tree","树");
        map.put("cloud","云");

        //System.out.println(map);
        //System.out.println(map.keySet());

/*      //方案一
        Set set = map.keySet(); //拿到所有的key
        Iterator iterator = set.iterator();
        while (iterator.hasNext()){
            String key = (String) iterator.next();
            System.out.println(key+": "+map.get(key)); //通过key获取到value*/

        //方案二
        Set set = map.entrySet();  //set里面装的是entry,entry包含了key和value
        Iterator iterator = set.iterator();
        while(iterator.hasNext()){
            Map.Entry entry = (Map.Entry) iterator.next();

            System.out.println(entry.getKey());
            System.out.println(entry.getValue());
        }


    }
}