Thursday, January 10, 2013

Quick guide for Migration of Commons HttpClient 3.x to HttpComponents HttpClient 4.x




As I agreed in the previous blog post for the migration guide of Commons HttpClient 3.x to HttpComponents HttpClient 4.x. Even I also took time to migrate, let me put my effort here so that someone can reap from it.

HttpComponents HttpClient is a HTTP/1.1 compliant HTTP agent implementation based on HttpCore. It also provides reusable components for client-side authentication, HTTP state management, and HTTP connection management. HttpComponents Client is a successor of and replacement for Commons HttpClient 3.x. Users of Commons HttpClient are strongly encouraged to upgrade.

Below table is the quick reference for the migration.


Commons HttpClient 3.x
HttpComponents HttpClient 4.x
import
import org.apache.commons.httpclient.Credentials;
import org.apache.commons.httpclient.Header;
import org.apache.commons.httpclient.HostConfiguration;
import org.apache.commons.httpclient.HttpClient;
import org.apache.commons.httpclient. MultiThreadedHttpConnectionManager;
import org.apache.commons.httpclient. UsernamePasswordCredentials;
import org.apache.commons.httpclient.auth.AuthScope;
import org.apache.commons.httpclient.methods.DeleteMethod;
import org.apache.commons.httpclient.methods.GetMethod;
import org.apache.commons.httpclient.methods.PostMethod;
import org.apache.http.Header;
import org.apache.http.HttpEntity;
import org.apache.http.HttpHost;
import org.apache.http.HttpResponse;
import org.apache.http.auth.AuthScope;
import org.apache.http.auth.Credentials;
import org.apache.http.auth.UsernamePasswordCredentials;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.conn.params.ConnRoutePNames;
import org.apache.http.entity.ContentType;
import org.apache.http.entity.StringEntity;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.util.EntityUtils;
HttpClient 
HttpClient client = new HttpClient(connectionManager);
DefaultHttpClient client = new DefaultHttpClient();



proxy configuration
client.getHostConfiguration().setProxy( proxyHost, proxyPort);
client.getState().setAuthenticationPreemptive( true);
Credentials cred = new  UsernamePasswordCredentials( proxyUser, proxyPassword);
client.getState().setProxyCredentials( AuthScope.ANY_HOST, proxyHost, cred)
client.getCredentialsProvider(). setCredentials(
 new AuthScope(proxyHost, proxyPort),
 new UsernamePasswordCredentials( proxyUser, proxyPassword));
HttpHost proxy = new HttpHost(proxyHost proxyPort);
client.getParams().setParameter( ConnRoutePNames.DEFAULT_PROXY, proxy);






POST
PostMethod post = new PostMethod();
post.setPath(url.getFile());
HttpPost post = new HttpPost(url.getFile());



POST Header
post.setRequestHeader(key, (String) headers.get(key));
post.addHeader(key, (String) headers.get(key));



POST Body
post.setRequestBody(message);
StringEntity messageEntity = new StringEntity( message,
 ContentType.create("text/plain", "UTF-8"));
      post.setEntity(messageEntity);



Execute POSt
client.executeMethod(post);
HttpHost targetHost = new HttpHost(url.getHost(), url.getPort(), url.getProtocol());
HttpResponse httpResponse = client.execute(targetHost, post);



Response Header
Header[] rspHeaders = post.getResponseHeaders();
Header[] rspHeaders = httpResponse.getAllHeaders();



Response Body
String responseMsg = post.getResponseBodyAsString()
StringBuffer buffer = new StringBuffer();
      BufferedReader reader = new BufferedReader(new InputStreamReader(httpResponse.getEntity().getContent()));
String dataLine = null;
while((dataLine = reader.readLine()) != null){
            buffer.append(dataLine);
}
String responseMsg =    buffer.toString();



GET
GetMethod getMethod = new GetMethod();
getMethod.setPath(url.getFile());
HttpGet httpGet = new HttpGet(url.getFile());



GET Header
getMethod.setRequestHeader(key, value);
httpGet.addHeader(key, value);



Execute GET
client.executeMethod(getMethod);
HttpHost targetHost = new HttpHost(url.getHost(), url.getPort(), url.getProtocol());
HttpResponse httpResponse = client.execute( targetHost, httpGet);




6 comments:

  1. Very useful Guide. Thanks for sharing.

    ReplyDelete
  2. Just what I need thanks :)

    ReplyDelete
  3. Thanks a lot very helpful

    ReplyDelete
  4. This was very useful when I upgraded our 3.1 lib to 4.3 (although some of the APIs have morphed *again* since 4.1->4.3!!)

    ReplyDelete
  5. Thanks this is what i was looking for.!!

    ReplyDelete
  6. Thanks, this post saved me. It's so useful

    ReplyDelete