Get cookies from HTTP connection

Byron KiourtzoglouNovember 11th, 2012Last Updated: December 29th, 2012

2 787 1 minute read

With this example we are going to demonstrate how to get cookies from an HTTP connection in Java. In short, to retrieve cookie information of a URL connection you should

Create a URL Object that represents the resource you want to access
Use the openConnection() API method of the URL Object to access connection specific parameters for the HTTP request
Use the getHeaderFields() API method from the connection Object to get the full list of Name-Value pairs representing the header fields of the specific connection
Cookie information should be – if present – under the “Set-Cookie” header field. Several Name-Value pairs may comprise the value of the specific cookie separated by semi-colons

You may get the specific cookie value as shown in the code snippet below.

package com.javacodegeeks.snippets.core;

import java.net.URL;
import java.net.URLConnection;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Set;

public class GetCookiesFromHTTPConnection {
	
	public static void main(String[] args) throws Exception {
		
		URL url = new URL("http://www.google.com:80");
		URLConnection conn = url.openConnection();

		Map<String, List<String>> headerFields = conn.getHeaderFields();

		Set<String> headerFieldsSet = headerFields.keySet();
		Iterator<String> hearerFieldsIter = headerFieldsSet.iterator();
		
		while (hearerFieldsIter.hasNext()) {
			
			 String headerFieldKey = hearerFieldsIter.next();
			 
			 if ("Set-Cookie".equalsIgnoreCase(headerFieldKey)) {
				 
				 List<String> headerFieldValue = headerFields.get(headerFieldKey);
				 
				 for (String headerValue : headerFieldValue) {
					 
					System.out.println("Cookie Found...");
					 
					String[] fields = headerValue.split(";\s*");

					String cookieValue = fields[0];
					String expires = null;
					String path = null;
					String domain = null;
					boolean secure = false;
					
					// Parse each field
					for (int j = 1; j < fields.length; j++) {
						if ("secure".equalsIgnoreCase(fields[j])) {
							secure = true;
						}
						else if (fields[j].indexOf('=') > 0) {
							String[] f = fields[j].split("=");
							if ("expires".equalsIgnoreCase(f[0])) {
								expires = f[1];
							}
							else if ("domain".equalsIgnoreCase(f[0])) {
								domain = f[1];
							}
							else if ("path".equalsIgnoreCase(f[0])) {
								path = f[1];
							}
						}
						
					}
					
					System.out.println("cookieValue:" + cookieValue);
					System.out.println("expires:" + expires);
					System.out.println("path:" + path);
					System.out.println("domain:" + domain);
					System.out.println("secure:" + secure);
					 
					System.out.println("*****************************************");
			
   
				 }
				 
			 }
			
		}
		
	}

}

Output:

Cookie Found...
cookieValue:NID=52=PwcXVmIE4acIM9BYOwXfjcjbl3K5eKBlmY2jx_-oIWY9ZPCQr0WsDNCjCc4kqmCLysK6qUn1DlVhpQCSpoQoSskvRdAV4fptSuc2esPhqMLC9yb9QCTQWBFgayL8YdeK
expires:Sun, 29-Apr-2012 19:50:17 GMT
path:/
domain:.google.gr
secure:false
*****************************************
Cookie Found...
cookieValue:PREF=ID=da4bc4ff59cbdda5:FF=0:TM=1319917817:LM=1319917817:S=857qQm4Nt5qON_en
expires:Mon, 28-Oct-2013 19:50:17 GMT
path:/
domain:.google.gr
secure:false
*****************************************

This was an example of how to get cookies from HTTP connection in Java.