Tuesday, June 1, 2010

JAXB-JSON Rest API using RESTEasy on JBoss EAP

In this second part of my evaluation of JBoss RESTEasy, I focus on adapting the JAXB-JSON samples provided by RESTEasy for JBoss Enterprise Application Platform 5.0.1.

Earlier I find myself to adapt the maven POM file to have the proper dependencies for the Twitter RESTEasy client.

Initially this simple JAXB-JSON sample had been designed to run on Jetty Web Server which run fine out-of-the box. However I had to make some modifications to the original project structure to have the code running as a simple eclipse project that can be deploy on JBoss EAP 5.0.X from RedHat (this will also work on Jboss community edition).

The new project (eclipse) structure looks as below:

Notice that I have also moved the code for both packages:  org.jboss.resteasy.annotations.providers.jaxb.json
at the root of my project, since I am not using the remaining code of the example.

I also made some additional adaptations for JBoss to some of the project files including:
  • pom.xml file
  • web.xml
I also added a small test suite to test the REST API operations using JUnit which will work after the first deployment (I run JBoss locally on http://localhost:8080).

By the way, make sure you have src/main/resources/META-INF/services/javax.ws.rs.ext.Providers included in your project.

Here is the content of my new pom.xml file for JBoss:

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">

            <id>maven repo</id>
            <name>maven repo</name>
        <!-- For resteasy -->
            <name>jboss repo</name>
        <!-- core library -->
            <!-- filter out unwanted jars -->
        <!-- optional modules -->
        <!-- modules already provided by Java 6.0 -->


I modified the web.xml for the URL looks more simple by removing the mapping to reasteasy:

<?xml version="1.0"?>
<!DOCTYPE web-app PUBLIC "-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN"

   <display-name>Archetype Created Web Application</display-name>







The JUnit code looks like this:

package org.jboss.resteasy.examples.test;
import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.URL;

import junit.framework.Assert;
import junit.framework.Test;
import junit.framework.TestCase;
import junit.framework.TestSuite;
public class LibraryTest extends TestCase
     * Create the test case
     * @param testName name of the test case
    public LibraryTest( String testName )
        super( testName );

     * @return the suite of tests being tested
    public static Test suite()
        return new TestSuite( LibraryTest.class );

     * Testing the Library REST API
    public void testGetMapped()  
     validateRESTCall("GET", "http://localhost:8080/jaxb-json/library/books/mapped");
     assertTrue( true );

    public void testGetBadger()  
     validateRESTCall("GET", "http://localhost:8080/jaxb-json/library/books/badger");
     assertTrue( true );
    private void validateRESTCall(String method, String url) {
     try {
         System.out.println("*** "+method);
         URL resURL = new URL(url);
         System.out.println("URL: " + url.toString());
         HttpURLConnection connection = (HttpURLConnection) resURL.openConnection(); 
         System.out.println("Content-Type: " + connection.getContentType());
         BufferedReader reader = new BufferedReader(new InputStreamReader(connection.getInputStream()));
         String line = reader.readLine();
         while (line != null)
            line = reader.readLine();
         Assert.assertEquals(HttpURLConnection.HTTP_OK, connection.getResponseCode());
     } catch (Exception err) { 
         System.out.print("Error in VHRResourceTest.validateRESTCall : " + err); 

To build I am using Maven (I recommend to install the maven eclipse plugin) with the goals mvn clean install compile package. Make sure also that before that you do a mvn eclipse:eclipse to update the dependencies in your project.

To deploy jaxb-json.war file from eclipse (so I don't have to manually copy the war file from the target folder), I have installed the JBoss eclipse plugin. As a result I can make it deployable (accessible by a right-click) and it appear in the Eclipse JBoss server view:

The REST API JSON Library resources are then accessible directly on a browser via http://localhost:8080/jaxb-json/library/books/mapped or http://localhost:8080/jaxb-json/library/books/badger.

If you want to compress your response, RESTEasy provides GZIP Compression/Decompression support using a very simple @GZIP annotation:

   public BookListing getBooksMapped()
      return getListing();

Just import the following class:

import org.jboss.resteasy.annotations.GZIP;

Overall the adaptation from Jetty to JBoss was easy and the documentation very clear.

Additional discussions, recommendations and information can be found on the JBoss Community.

For an example of using REST architecture for Mobile Applications (HealthCare) see this post.

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