Consuming Web Services with Jakarta Commons HttpClient

Consuming web services with Jakarta Commons HttpClient can be useful to reuse all the API provided by HttpClient.
The example below query a web service that requires HTTP authentication. We could also use that mechanism for NTLM or proxy authentication.

More generally, for all authentication made in the HTTP layer rather than the SOAP layer, HttpClient is a good candidate.

To run this code you need the library of HttpClient and HttpCore. I used version 4.0 and 4.0.1

http://hc.apache.org/downloads.cgi

you also need commons codec: I used version 1.4

http://commons.apache.org/codec/download_codec.cgi

To consume Web Services protected with NTLM (sic). You can refer to this page: http://www.luigidragone.com/networking/ntlm.html

So here's the code:


package org.apache.http.examples.client;

import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.auth.AuthScope;
import org.apache.http.auth.UsernamePasswordCredentials;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.entity.StringEntity;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.message.BasicHeader;
import org.apache.http.util.EntityUtils;

/**
* A simple example that uses HttpClient to execute an HTTP request against a
* target site that requires user authentication.
*/
public class ClientAuthentication {

private static final String XML_DATA =
"<?xml version=\"1.0\" encoding=\"UTF-8\"?>" + "<soap:Envelope xmlns:soap=\"http://schemas.xmlsoap.org/soap/envelope/\"> "
+ "<soap:Body xmlns:ns1=\"http://xmlns.oracle.com/SensorBPEL\">" + "<ns1:SensorBPELProcessRequest><ns1:input>toto</ns1:input></ns1:SensorBPELProcessRequest>"
+ "</soap:Body></soap:Envelope>";

public static void main(String[] args) throws Exception {
DefaultHttpClient httpclient = new DefaultHttpClient();

httpclient.getCredentialsProvider().setCredentials(new AuthScope("ch0016188", 8888), new UsernamePasswordCredentials("frederic_agneray", "pass"));

HttpPost httpPost = new HttpPost("http://ch0016188:8888/gateway/services/SID0003006");
httpPost.setHeader(new BasicHeader("Content-Type", "text/xml;charset=UTF-8"));
httpPost.setHeader(new BasicHeader("SOAPAction", "process"));
StringEntity s = new StringEntity(XML_DATA, "UTF-8");
httpPost.setEntity(s);

System.out.println("executing request" + httpPost.getRequestLine());
HttpResponse response = httpclient.execute(httpPost);
HttpEntity entity = response.getEntity();

System.out.println("----------------------------------------");
System.out.println(response.getStatusLine());
if (entity != null) {
System.out.println("Response content length: " + entity.getContentLength());
System.out.println(EntityUtils.toString(response.getEntity()));
}
if (entity != null) {
entity.consumeContent();
}

// When HttpClient instance is no longer needed,
// shut down the connection manager to ensure
// immediate deallocation of all system resources
httpclient.getConnectionManager().shutdown();
}
}