Jakarta Commons Cookbook

11.7. Making an HTTP POST Request

Problem

You need to supply parameters to a script or servlet using HTTP POST.

Discussion

Create a PostMethod and call setParameter( ) or addParameter() before you execute the method. The PostMethod will send a request with a Content-Type header of application/x-www-form-urlencoded, and the parameters will be sent in the request body. The following example demonstrates the use of PostMethod to send parameters:

               import org.apache.commons.httpclient.HttpClient;
import org.apache.commons.httpclient.HttpException;
import org.apache.commons.httpclient.NameValuePair;
import org.apache.commons.httpclient.methods.PostMethod;

HttpClient client = new HttpClient( );
        
// Create POST method
String url = "http://www.discursive.com/cgi-bin/jccook/param_list.cgi";
PostMethod method = new PostMethod( url );

// Set parameters on POST    
               method.setParameter( "test1", "Hello World" );
               method.addParameter( "test2", "This is a Form Submission" );
               method.addParameter( "Blah", "Whoop" );
               method.addParameter( new NameValuePair( "Blah", "Whoop2" ) );

// Execute and print response
client.executeMethod( method );
String response = method.getResponseBodyAsString( );
System.out.println( response );

method.releaseConnection( );

The param_list.cgi CGI script echoes all parameters received, and from the following output, you can see that three parameters were supplied to this script:

These are the parameters I received: test1: Hello World test2: This is a Form Submission Blah: Whoop ...