How to set custom User-Agent with apache http client library 4.1?

Question

How to make HTTPClient use custom User-Agent header?

The following code submits empty user-agent. What am I missing?

import java.io.IOException;  import org.apache.http.HttpEntity; import org.apache.http.HttpResponse; import org.apache.http.client.ClientProtocolException; import org.apache.http.client.HttpClient; import org.apache.http.client.methods.HttpGet; import org.apache.http.impl.client.DefaultHttpClient; import org.apache.http.params.CoreProtocolPNames; import org.apache.http.protocol.BasicHttpContext; import org.apache.http.protocol.HttpContext; import org.apache.http.util.EntityUtils;  public class TestHTTP {          public static void main(String[] args) throws ClientProtocolException, IOException {         HttpGet request = new HttpGet("http://tool.keepmeapi.com/echo");          HttpContext HTTP_CONTEXT = new BasicHttpContext();         HTTP_CONTEXT.setAttribute(CoreProtocolPNames.USER_AGENT, "Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.2.13) Gecko/20101206 Ubuntu/10.10 (maverick) Firefox/3.6.13");         request.setHeader("Referer", "http://www.google.com");          HttpClient httpClient = new DefaultHttpClient();         HttpResponse response = httpClient.execute(request, HTTP_CONTEXT);          if (response.getStatusLine().getStatusCode() < 200 || response.getStatusLine().getStatusCode() >= 400) {             throw new IOException("Got bad response, error code = " + response.getStatusLine().getStatusCode());         }          HttpEntity entity = response.getEntity();         if (entity != null) {             System.out.println(EntityUtils.toString(entity));             EntityUtils.consume(entity);         }     }  } 

Answer 1

Note: The solution is for users using the old httpcomponents 4.2 and before.

The line

request.setHeader("User-Agent", "MySuperUserAgent");

is missing. Add it and enjoy.

Answer 2

Note: Starting from httpcomponents 4.3 this solution is deprecated.

You can also set a global user agent value instead of per request:

String userAgent = "NewUseAgent/1.0"; HttpClient httpClient = new DefaultHttpClient(); httpclient.getParams().setParameter(CoreProtocolPNames.USER_AGENT, userAgent);