Jakarta Commons Cookbook

11.4. Sending Parameters in a Query String

Problem

You need to send query parameters in a URL.

Solution

Set the query string using the setQueryString( ) method on an instance of HttpMethod. Use URIUtil to encode any text included in a URL. The following example puts two parameters on the query string:

               import org.apache.commons.httpclient.HttpClient;
import org.apache.commons.httpclient.HttpException;
import org.apache.commons.httpclient.HttpMethod;
import org.apache.commons.httpclient.NameValuePair;
import org.apache.commons.httpclient.methods.GetMethod;
import org.apache.commons.httpclient.util.URIUtil;

HttpClient client = new HttpClient( );

String url = "http://www.discursive.com/cgi-bin/jccook/param_list.cgi";

HttpMethod method = new GetMethod( url );

// Set the Query String with setQueryString( )
method.setQueryString(URIUtil.encodeQuery("test1=O Reilly&blah=Whoop"));
System.out.println( "With Query String: " + method.getURI( ) );

client.executeMethod( method );

System.out.println( "Response:\n " + method.getResponseBodyAsString( ) );
method.releaseConnection( );

The param_list.cgi CGI script echoes all parameters received, and from the following output, you can see how URIUtil encodes the first parameter:

With Query String: http://www.discursive.com/cgi-bin/jccook/param_list.
cgi?test1=O%20Reilly&blah=Whoop
Response:
 These are the parameters I received:

test1:
  O Reilly
blah:
  Whoop

Tip

The question mark is understood, and you do not need to supply a leading question mark to the ...