THIS IS A TEST INSTANCE. ALL YOUR CHANGES WILL BE LOST!!!!
So you've got 5 minutes and want to see how much you can do with Eclipse and Geronimo v2, huh? If so, you won't find much here, then unless you have already installed 2, don't you? Install Eclipse and Geronimo Eclipse plugin as described at Geronimo Eclipse Plugin Installation Instructions. It makes a huge difference. and 5 minutes seem quite enough. Let's check it out!
Read some introductory material on how to define Geronimo in Eclipse at Geronimo Eclipse Plugin Usage Instructions
Create Enterprise Application Project
Start from creating an enterprise application project. Select File > New, select Project... (or alternatively press Ctrl-N) and in the popup window select select Enterprise Application Project in J2EE category.
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In the EAR Application Project wizard type in SampleEAR as the project name and select Apache Geronimo v2.0 in Target Runtime. Leave the rest as is.
Press Next twice.
In the New EAR Application Project window select the Generate Deployment Descriptor checkbox.
Press Next three times.
Fill in the Geronimo Deployment Plan's fields with the following values (you want to know more why they're important? Read it on in the Geronimo documentation - http://cwiki.apache.org/GMOxDOC12/deployment-plans.html1.2 Documentation - Deployment plans):
- Group Id: sampleear
- Artifact Id: sample-ear
- Artifact Type: ear
Press Finish.
When asked about changing to the Java EE perspective, press Yes. You may want to select the Remember my decision checkbox to avoid dealing with it in the future.
...
You should now have the following project structure.
| Note |
|---|
Don't worry about the error cvc-complex-type.2.4.b: The content of element 'application' is not complete... for now. You'll fix it in the next step when you define an ejb module (and webapp module afterwards). |
Create EJB project
The next step is to create an EJB project to hold your EJBs. Press Ctrl-N and select EJB Project in EJB category.
...
- Group Id: sampleear
- Artifact Id: sample-ejb
- Artifact Type: ejb
Press Finish.
You should now have the following project structure.
| Note |
|---|
Remove ejbModule/META-INF/openejb-jar.xml file in the SampleEJB project as it leads to causes deployment issues. |
Create Dynamic Web Project
The next step is to create a Dynamic Web project to hold your web application. Press Ctrl-N and select Dynamic Web Project in Web category.
...
- Group Id: sampleear
- Artifact Id: sample-war
- Artifact Type: war
Press Finish.
You should now have the following project structure.
Create Stateless Session EJB
Every stateless session ejb has its own business interface. There're three types of business interfaces - @Remote, @Local and @WebService - and their combinations. Suffice to say that every EJB development starts from defining a business interface and implementing it by a bean implementation class.
Create remote business interface
Right-click on the SampleEJB project and select New > Interface and fill it in with the following values:
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| Code Block | ||||||||
|---|---|---|---|---|---|---|---|---|
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package sampleear;
import javax.ejb.Remote;
@Remote
public interface RemoteBusinessInterface {
public String sayHello(String name);
}
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Create bean class
Right-click on the SampleEJB project and select New > Class and fill it in with the following values:
...
| Code Block | ||||||||
|---|---|---|---|---|---|---|---|---|
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package sampleear;
import javax.ejb.Stateless;
@Stateless
public class MyStatelessSessionBean implements RemoteBusinessInterface {
public String sayHello(String name) {
return getClass().getName() + " says hello to " + name + ".";
}
}
|
Web application development
The time has come to use the ejb in the web application. We create a jsp page index.jsp that executes a servlet MyServlet that in turn executes the ejb MyStatelessSessionBean.
Create welcome page - index.jsp
Right-click on the SampleWAR project and select New > JSP. Name it index.jsp. Press Finish.
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| Code Block | ||||||||
|---|---|---|---|---|---|---|---|---|
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<%@ page language="java" contentType="text/html; charset=ISO-8859-1" pageEncoding="ISO-8859-1"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>5-minute introductionTutorial toon enterpriseEnterprise applicationApplication developmentDevelopment with Eclipse and Geronimo</title>
</head>
<body>
<form action="${pageContext.request.contextPath}/sayHello">
<input type="text" name="name" /><input type="submit" value="Press me!" />
</form>
</body>
</html>
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Create servlet - MyServlet
Since the servlet calls the EJB, the web project the servlet is in depends on the EJB project. Let's define the dependency.
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| Code Block | ||||||||
|---|---|---|---|---|---|---|---|---|
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package sampleear;
import java.io.IOException;
import javax.ejb.EJB;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
public class MyServlet extends javax.servlet.http.HttpServlet implements javax.servlet.Servlet {
static final long serialVersionUID = 1L;
@EJB
RemoteBusinessInterface remoteBusinessIntf;
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
String name = request.getParameter("name");
if (name == null || name.length() == 0) {
name = "anonymous";
}
response.getWriter().write(remoteBusinessIntf.sayHello(name));
}
}
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Create application.xml
| Note |
|---|
It appears that the file is not created by default and the application could not be deployed to any Java EE 5-compliant application server, Geronimo including. We need to define it manually. Don't know whether it's a bug in Eclipse or Geronimo Eclipse Plugin. |
Create application.xml deployment descriptor in EarContent/META-INF directory of the SampleEAR project as follows.
| Code Block | |
|---|---|
| xml | xml |
| borderStyle | solid |
| title | application.xml |
<?xml version="1.0" encoding="ASCII"?>
<application xmlns="http://java.sun.com/xml/ns/javaee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:application="http://java.sun.com/xml/ns/javaee/application_5.xsd"
xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/application_5.xsd"
version="5">
<display-name>SampleEAR</display-name>
<module>
<ejb>SampleEJB.jar</ejb>
</module>
<module>
<web>
<web-uri>SampleWAR.war</web-uri>
<context-root>/SampleWAR</context-root>
</web>
</module>
</application>
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Run it!
After a very hard 4-minute development it's time to give it a shot and see if it works. Not much time left so hurry up!
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After a few seconds, Geronimo should be up and running with the enterprise application published. Open up the browser of your choice and go to http://localhost:8080/SampleWAR
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Type in any name you want, e.g. Jacek and press Press me! button.
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