EJB Hello world example
Creating and testing the "Hello World" Example is the very first step towards learning of any application or programming language. In the given example we are going to show you, how to create your first hello world example in EJB and testing it.
You can also create a hello world example to test your EJB environment setup. This simple application will required three different files to print the message.
- SessionBeanRemote.java:- This is the Remote interface which extends javax.ejb.EJBObject package. These are similar to RMI Remote interface. The use of remote interface is particularly helpful in providing business-specific functionality of an EJB.Here @Remote is the annotation used to declare the interface as Remote.
String getAddress(); String getCompanyname(); String getResult():-These are the methods which is to be defined in the bean.
2. SessionBeanBean.java:-This
is the bean of type session in which we have defined the body of the
method which were declared in
the
interface named
SessionBeanRemote.java.@Stateless is the annotation used to declare the
bean as a session type.
3. Main.java:-This is the
client application from which we can access the methods which are defined
in the bean.@EJB is the
annotation
used for
configuring the EJB values for a field and method.
SessionBeanRemote.java
package ejb; import javax.ejb.Remote; @Remote public interface SessionBeanRemote { String getResult(); String getAddress(); String getCompanyname(); }
SessionBeanBean.java
package ejb; import javax.ejb.Stateless; @Stateless public class SessionBeanBean implements SessionBeanRemote,SessionBeanLocal { public String getResult() { return "Hello World"; } public String getAddress() { return "Sec-3,D-16/116,Rohini"; } public String getCompanyname() { return "Roseindia.net Pvt.Ltd."; } }
Main.java
package enterpriseappee5; import ejb.SessionBeanRemote; import javax.ejb.EJB; public class Main { @EJB private static SessionBeanRemote sessionBeanBean; public static void main(String[] args) { System.out.println("Displaying Message using EJB:"); System.out.println("================================="); System.err.println("Name of the Company is : =" + sessionBeanBean.getCompanyname()); System.err.println("Address of the Company is : =" + sessionBeanBean.getAddress()); System.err.println("Message is : =" + sessionBeanBean.getResult()); System.out.println("================================="); } }
Output of the program
Displaying Message using EJB:
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