BE THE CODER > Tools and Libs > Commons Http Client

Commons Http Client is a HTTP agent implementation in java supporting client-side authentication, HTTP state management and HTTP connection management. This requires the libraries httpclient-4.1.2.jar, httpcore-4.1.2.jar, httpmime-4.1.2.jar, httpclient-cache-4.1.2.jar, commons-codec.jar, commons-io-1.3.2.jar and commons-logging-1.1.1.jar to be in classpath. The following example shows how to create a response Interceptor.

File Name :	com/bethecoder/tutorials/commons_httpclient/ResponseInterceptorTest.java
Author :	Sudhakar KV
Email :	[email protected]


package com.bethecoder.tutorials.commons_httpclient;



import java.io.ByteArrayInputStream;

import java.io.IOException;

import java.io.InputStream;



import org.apache.commons.io.IOUtils;

import org.apache.http.HttpEntity;

import org.apache.http.HttpException;

import org.apache.http.HttpResponse;

import org.apache.http.HttpResponseInterceptor;

import org.apache.http.client.ClientProtocolException;

import org.apache.http.client.ResponseHandler;

import org.apache.http.client.methods.HttpGet;

import org.apache.http.entity.HttpEntityWrapper;

import org.apache.http.impl.client.BasicResponseHandler;

import org.apache.http.impl.client.DefaultHttpClient;

import org.apache.http.protocol.HttpContext;



public class ResponseInterceptorTest {



  /**

   * @param args

   * @throws IOException 

   * @throws ClientProtocolException 

   */

  public static void main(String[] args) throws ClientProtocolException, IOException {

    DefaultHttpClient httpclient = new DefaultHttpClient();

    HttpGet httpget = new HttpGet("http://localhost:8080/HTTP_TEST_APP/print_headers.jsp");

    System.out.println("Requesting : " + httpget.getURI());



    try {

      //Add response Interceptor

      httpclient.addResponseInterceptor(new HttpResponseInterceptor() {

        

        @Override

        public void process(HttpResponse response, HttpContext context)

            throws HttpException, IOException {

          

          //Add header

          response.addHeader("Tampered-By", "UppercaseEntity Response Interceptor");

          

          //Set a new entity wrapper

          response.setEntity(new UppercaseEntity(response.getEntity()));

        }

      });

      

      ResponseHandler<String> responseHandler = new BasicResponseHandler();

            String responseBody = httpclient.execute(httpget, responseHandler);

            

      System.out.println("responseBody : " + responseBody);

    } finally {

       httpclient.getConnectionManager().shutdown();

    }



  }



}



class UppercaseEntity extends HttpEntityWrapper {



    public UppercaseEntity(final HttpEntity entity) {

        super(entity);

    }



    public InputStream getContent() throws IOException, IllegalStateException {

      InputStream responseStream = wrappedEntity.getContent();

    String resposeString = IOUtils.toString(responseStream);

    

    //Get response in upper case

        return new ByteArrayInputStream(resposeString.toUpperCase().getBytes());

    }

}

How to add Response Interceptor