package sun;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
import java.util.Set;
/**
* 遍历集合常见的两种方式
* @author Administrator
*/
public class MapTest
{
public static void main(String[] args)
{
Map<String,String> map = new HashMap<String,String>();
map.put("a","aa");
map.put("b","bb");
map.put("c","cc");
map.put("d","dd");
//这是第一种遍历map的方式,先获得map的key,然后普通过key的值来得到value的值
Set<String> set = map.keySet();
for(Iterator<String> iter = set.iterator();iter.hasNext();)
{
String key = iter.next();
String value = map.get(key);
System.out.println(key + ":" + value);
}
System.out.println("----------------------------------------");
//这是第二种遍历map的方式,一次性获得map的key和value值
Set<Map.Entry<String,String>> set2 = map.entrySet();
for(Iterator<Map.Entry<String,String>> iter2 = set2.iterator();iter2.hasNext();)
{
Map.Entry<String,String> entry = iter2.next();
String key = entry.getKey();
String value = entry.getValue();
System.out.println(key + ":"+ value);
}
}
}
Two common ways through the collection
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Origin blog.csdn.net/qq_31960623/article/details/104079838
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