Get HTTP response header information via URLConnection in Java

This article shows how to get the HTTP response header information through URLConnection

1. Get header information from the response

URL obj = new URL ("http://www.bianceng.cn");
URLConnection conn = Obj.openconnection ();
map<string, list<string>> map = Conn.getheaderfields ();

2. Get the server information from the response header

map<string, list<string>> map = Conn.getheaderfields ();
 list<string> Server = map.get ("server");

Complete example

Package com.qiyadeng.http;
Import Java.net.URL;
Import java.net.URLConnection;
Import java.util.List;
     
Import Java.util.Map;
     
                public class Gethttpresponseheader {public static void main (string[] args) {try {
                URL obj = new URL ("http://www.bianceng.cn");
                URLConnection conn = Obj.openconnection ();
     
                map<string, list<string>> map = Conn.getheaderfields ();
     
                SYSTEM.OUT.PRINTLN ("Show response header information ... \ n");  For (map.entry<string, list<string>> entry:map.entrySet ()) {System.out.println ("Key
                : "+ entry.getkey () +", Value: "+ entry.getvalue ());
                System.out.println ("\ n use key to get response header information \ n");
     
                list<string> Server = map.get ("server"); if (server = = null) {System.out.println ("KeY ' Server ' is not found! ');}
                        else {for (String values:server) {System.out.println (values);
        A catch (Exception e) {e.printstacktrace ()); }
     
  }
     
}

Output

Show Response header information ...

Key:null, value: [http/1.1 OK]
key:x-pingback, value: [http://www.bianceng.cn/xmlrpc.php]
key:date, Va Lue: [Sun, Mar 2013 12:16:26 GMT]
key:transfer-encoding, value: [chunked]
key:connection, value: [Close]
Key:content-type, Value: [text/html; Charset=utf-8]
Key:server, Value: [apache/2.2.3 (CentOS)]
key:x-powered-by, value: [php/5.2.17]
    
use Key to get response header information ...
    
apache/2.2.3 (CentOS)

Source: http://www.qiyadeng.com/