Sunday, March 27, 2016

Java Networking Examples : How To Get HTTP Header Information of URL

Posted By: Unknown 6:39 AM Leave a Reply

Intro

This examples will demonstrates how to get header information of URL such as status code, response code, content type, and etc.

To get a header information of URL, you can use HttpURLConnection.getHeaderFields() method.

Examples

package com.freesamplecode.java.networking;

import java.io.IOException;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;
import java.util.Iterator;
import java.util.Map;
import java.util.Set;

public class GetHeaderInformationURLDemo {
 public static void main(String[] args){
  
  try {
   //create URL object
   URL url = new URL("http://free-samplecode.blogspot.com/p/java.html");
   
   //open URL connection
   HttpURLConnection httpUrlConnection =  (HttpURLConnection) url.openConnection();
   
   //get all URL header informations
   Map headerField = httpUrlConnection.getHeaderFields();
   
   Set set = headerField.entrySet();
   
   Iterator it = set.iterator();
   
   while(it.hasNext()){
    System.out.println(it.next());
   }
   

  } catch (MalformedURLException e) {
   e.printStackTrace();
  } catch (IOException e) {
   e.printStackTrace();
  }
 }
}

Output

null=[HTTP/1.1 200 OK]
Expires=[Sun, 27 Mar 2016 13:31:17 GMT]
X-XSS-Protection=[1; mode=block]
Last-Modified=[Sun, 27 Mar 2016 13:15:17 GMT]
Connection=[Keep-Alive]
Server=[GSE]
X-Content-Type-Options=[nosniff]
Cache-Control=[private, max-age=0]
Date=[Sun, 27 Mar 2016 13:31:17 GMT]
Vary=[Accept-Encoding]
Transfer-Encoding=[chunked]
Content-Type=[text/html; charset=UTF-8]
Accept-Ranges=[none]