获取HttpResponseHeader属性 - JAVA

/**
*
* @author Cache John
* @email
*
*/
public class GetHttpResponseHeader
{

public static void main(String[] args)
{
try
{

URL obj = new URL("http://www.huawei.com");
URLConnection conn = obj.openConnection();

Map> map = conn.getHeaderFields();

System.out.println("显示响应Header信息\n");

for (Map.Entry> entry : map.entrySet())
{
System.out.println("Key : " + entry.getKey() + " ,Value : " + entry.getValue());
}

System.out.println("\n使用key获得响应Header信息 \n");
List server = map.get("Server");

if (server == null)
{
System.out.println("Key 'Server' is not found!");
}
else
{
for (String values : server)
{
System.out.println(values);
}
}

}
catch (Exception e)
{
e.printStackTrace();
}

}