Weblogic / Java EE6 FAQ and Guides

Install and Launch JavaDB

1. Get this archive that contains JavaDB 10.x + a sample database : javadb.zip,
2. Unzip it somewhere,
3. go to <java db install dir>/bin and run startNetworkServer.bat
4. Notice the presence in the bin dir of a directory named "sample". This is an example database. By default, the derby server locates databases in the bin dir.

Add the connection to the DB admin tool in Eclipse java EE perspective

1. In Eclipse, in the Java EE perspective, locate a tab called "Data Source Explorer", right click on "Database Connections" and choose "New" in order to add a new connection.
2. In the next dialog, type in "Der" and choose "Derby" as the database type, click next
3. Then you must indicate which JDBC driver you are going to use. Choose "Derby Client JDBC driver 10.1", but this is not enough, you need to set the proper jar file to use. So click on the small rounded button at the right '"new driver definition", then on the "jar list" tab. Remove proposed jar and click on the "add jar/zip" button on the right.
4. Go to <java db install dir>/lib and select the derbyclient.jar file.
5. Enter the sample database infos: sample/localhost/1527/app/app (app is both the value for user and for password). Unselect the "create database" button. Click on the "test connection" button on the right.

Add the DataSource to Weblogic 12c

In WebLogic 12c, run the admin server from the windows start menu, then open the weblogic admin console (also from start menu). 

1. Go to the "source de données"/datasources link in the main page. Click on it
2. Use the nouveau/new button in order to add a datasource,
3. Select "source de données generiques"/generic datasource in the drop down menu
4. Next dialog : enter a name for the database : I suggest "SerbySample", enter a JNDI name for accessing the database from a java EE application. I suggest "sample".  Choose "Derby" as the database type. CLick next.
5. Next dialog click next in order to validate the JDBC driver proposed by default (WebLogic comes with the Derby driver pre-installed)
6. Next dialog: click next (transactions options),
7. Next dialog: enter the same infos as when you connected the database to Eclipse: sample/localhost/1527/app/app cick Next    
8. Next dialog, click "Test the connection", if everything is ok, click next,
9. Next dialog, check the AdminServer as a target for this database. Do not forget to select the target server otherwise your datasource will not be exposed to external applications.
10. Click finish.
     

Installing a JMS queue on WebLogic

Good guide on how to setup a JMS queue here : 

• For weblogic 12c (english) : http://www.oracle.com/webfolder/tech...erviceWLS.html
• FOr weblogic 10 (french) : http://blog.touret.info/blog/index.php/post/2011/09/22/Mise-en-oeuvre-d-une-file-d-attente-JMS-sur-Weblogic-10.3 

Writing a message driven bean

Note: Message Driven Beans are not supported by the JavaEE 6 "Web profile" (all in one projects with jsf/jsp/servlets/ejb/jpa in one single project, deployed as a single war file). For MDB you need to create an EAR project, and an EJB project (maybe with JPA facet), and maybe a Dynamic Web project (for jsf/jsp/servlets). The MDB should be added into the EJB project. The client servlet we demonstrate here should be added in the dynamic web project.
 

Normally the Eclipse wizard should ask you for the names of the connexion factory + destination. Here is an example of a MDB that works with the client from the next section.

•  Check that the name used in the MDB is the same as the JNDI name you can find in the JNDI tree for your weblogic server. You can do that by looking at the weblogic admin console, on the left, click on "base_domain", then "servers", then in the main page click on the name of your server, then in the main window you should have something like "JNDI tree"... Click on that, a new tab opens in which you can explore the names objects on your server. In the small tree, click on "weblogic" then "jms" then on the connection factory and destination. You will find in the detailed view the JNDI names.

Example MDB:

package sessions;

import javax.ejb.ActivationConfigProperty;
import javax.ejb.MessageDriven;
import javax.jms.JMSException;
import javax.jms.Message;
import javax.jms.MessageListener;
import javax.jms.TextMessage;

@MessageDriven(
		activationConfig = { @ActivationConfigProperty(
				propertyName = "destinationType", propertyValue = "javax.jms.Queue"
		) }, 
		mappedName = "weblogic.jms.DemoQueue")
public class TestMDB implements MessageListener {

    public TestMDB() {
        // TODO Auto-generated constructor stub
    	System.out.println("TestMDB : NEW INSTANCE BUILT !");
    }

    public void onMessage(Message message) {
        if(message instanceof TextMessage) {
    
        	
        	TextMessage txtMsg = (TextMessage) message;
        	try {
				String msg = txtMsg.getText();
				System.out.println("Message received: " + msg);
				System.out.println("Processing message");
		    	Thread.sleep(5000);
		    	System.out.println("End of processing message");
			} catch (Exception e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}
        	
        	
        }
        
    }

}

 Writing a client for a weblogic queue

Here is an example of a servlet that sends messages to the previous message driven bean. In fact it doesn't know the actual receiver of the message, it just knows the destination where the message is being sent.

Again, double check the names of the connection factory and of the destination. They should exactly match the ones in the weblogic admin console and the ones in the MDB.

package servlets;

import java.io.IOException;
import java.util.Collection;
import java.util.logging.Level;
import java.util.logging.Logger;

import javax.annotation.Resource;
import javax.ejb.EJB;
import javax.jms.Connection;
import javax.jms.ConnectionFactory;
import javax.jms.JMSException;
import javax.jms.MessageProducer;
import javax.jms.Queue;
import javax.jms.Session;
import javax.jms.TextMessage;
import javax.servlet.ServletException;
import javax.servlet.ServletOutputStream;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import entities.Book;


/**
 * Servlet implementation class DemoServlet
 */
@WebServlet("/DemoServlet")
public class DemoServlet extends HttpServlet {
	private static final long serialVersionUID = 1L;

	
    // For JMS and the MessageDrivenBean
    @Resource(name = "weblogic.jms.DemoQueue")
    private Queue demoQueue;
    @Resource(name = "weblogic.jms.democonnectionfactory")
    private ConnectionFactory demoMessageFactory;
    
 
    public DemoServlet() {
        super();
        // TODO Auto-generated constructor stub
    }


	protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
                // Test sending a message with JMS to a Message Driven Bean
		try {
			sendJMSMessageToDemoQueue("This is a message sent using JMS and a MDB !");
		} catch (JMSException e) {
			e.printStackTrace();
		}
	}

	

	 private TextMessage createJMSMessageForjmsLoggingMessages(Session session, String messageData) throws JMSException {  
	        TextMessage message = session.createTextMessage();
	        message.setText(messageData);
	        return message;
	    }

	    private void sendJMSMessageToDemoQueue(String messageData) throws JMSException {
	        Connection connection = null;
	        Session session = null;
	        try {
	            connection = demoMessageFactory.createConnection();
	            session = connection.createSession(false, Session.AUTO_ACKNOWLEDGE);
	            MessageProducer messageProducer = session.createProducer(demoQueue);
	            messageProducer.send(createJMSMessageForjmsLoggingMessages(session, messageData));
	            String messageClient = "Message sent :" + messageData;
	            System.out.println(messageClient);
	        } finally {
	            if (session != null) {
	                try {
	                    session.close();
	                } catch (JMSException e) {
	                    Logger.getLogger(this.getClass().getName()).log(Level.WARNING, "Cannot close session", e);
	                }
	            }
	            if (connection != null) {
	                connection.close();
	            }
	        }
	    }
}