遍历map

package l6.e5.map;

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

public class MapTest5My2
{
	public static void main(String[] args)
	{
		HashMap<String,String> map = new HashMap<String,String>();
		
		map.put("a", "aa");
		map.put("b", "bb");
		map.put("c", "cc");
		map.put("d", "dd");
		
		Set<String> set = map.keySet();
		//keyset 1 
		for (String key : set) {
			System.out.println("key= "+ key + " and value= " + map.get(key));
		}
		//keyset 2
		Iterator<String> it=set.iterator();
		while (it.hasNext()) {
			String key = (String) it.next();
			String value=map.get(key);
			System.out.println(key+":"+value);
			
		}
		
		//entryset
		Set<Map.Entry<String, String>> set2= map.entrySet();
		
		for (Map.Entry<String, String> entry : set2) {
			System.out.println("key :" + entry.getKey() + " and value :" + entry.getValue());
		}
		
		
		
	}
}