Problem for Posting an Article to MediaWiki Server

I want to post articles to the MediaWiki server via the httpclient of
apache. I used the following code to do that, but failed.

Can anybody help me ? Or did such things successfully?

import java.io.IOException;

import org.apache.commons.httpclient.DefaultHttpMethodRetryHandler;
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;
import org.apache.commons.httpclient.params.HttpMethodParams;

public class Post {

    public static void main(String[] args) {
        HttpClient client = new HttpClient();
        PostMethod post = new
postMethod("http://localhost/mediawiki/index.php?title=Haha&action=submit");
        post.getParams().setParameter(HttpMethodParams.RETRY_HANDLER,
         new DefaultHttpMethodRetryHandler(3, false));
        post.getParams().setIntParameter(HttpMethodParams.SO_TIMEOUT, 5000);
        NameValuePair[] data = {
          new NameValuePair("wpTextbox1", "== hi =="),
          new NameValuePair("wpSummary",""),
          new NameValuePair("wpSection","Save page"),
          new NameValuePair("wpEdittime",""),
          new NameValuePair("wpSave","Save")

        };
        post.setRequestBody(data);
        try {
            int statusCode1 = client.executeMethod(post);
        } catch (HttpException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }

        System.out.println("statusLine>>>" + post.getStatusLine());
        post.releaseConnection();
    }

}