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1. Right Click on the ejb package and create a new Remote interface CountryCapital as shown in the figure
   
   
   
   
   
   
2. Enter the fields as shown in the figure and select Finish.
   
   
   
   
   
   
3. Add the following code as shown below

   Code Block
   title CountryCapital.java borderStyle solid
   package ejb; import javax.ejb.Remote; @Remote public interface CountryCapital { public String capitalName(String countryName); }

   Here @Remote is an annotation used to declare the interface as a Remote Interface.
   
4. Similarly create a Local interface CountryCapitalLocal. Add the following code to the interface
   

   Code Block
   title CountryCapitalLocal.java borderStyle solid
   package ejb; import javax.ejb.Local; @Local public interface CountryCapitalLocal { public String capitalName(String countryName); }

   
   Similarly in this code we have @Local annotation which declares this interface as local.
   
   In remote as well as local interface we have the declaration for only one Business method. So only this method will be visible to the application client. Methods other than capitalName if implemented in the Bean class will be private to Bean class and will not be visible to application client.
   
   
5. Next step is to create a Bean Class which will implement the Business method to be executed. Right Click on the jsf package and create a new class.
   
   
   
   
   
   
6. Enter the class name as CountryCapitalBean.
   
   
   
   
   
   
7. Populate the bean class with the code as follows
   

   Code Block
   title CountryCapitalBean.java borderStyle solid
   package ejb; import javax.ejb.Stateless; @Stateless public class CountryCapitalBean implements CountryCapital,CountryCapitalLocal{ public String capitalName(String countryName) { String capital=new String("No such country"); if (countryName.equalsIgnoreCase("India")) { capital="New Delhi"; } if (countryName.equalsIgnoreCase("United States Of America")) { capital="Washington DC"; } if (countryName.equalsIgnoreCase("China")) { capital="Bejing"; } return capital; } }

This completes the development of EJB application.

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1. Select File->New->Project->Java->Java Project. Select Next.
   
   
   
   
   
   
2. In the New Project Window give the Project name ss ApplicationClient and select Next.
   
   
   
   
   
   
3. On the Java Settings window. Select the Projects tab and click add.
   
   
   
   
4. Check the box for SimpleEJB and Select OK.
   
   
   !
   
   
   
5. This will add the SimpleEJB project to the build path of the Application Client as shown in the figure. Select Finish.
   
   
   !
   
   
   

   Tip
   title Why to add EJB project to build path :(
   This is because the build path is used to find the classes referenced by your Client source code. These classes will be required for compilation of Client source code.

6. Right click on package appclient and create a new Java Class.
   
   
   !
   
   
   
7. Give the class name as ApplicationClient as shown in the figure. Select Finish.
   
   
   !
   
   
   
8. Populate the ApplicationClient.java with the following code
   

   Code Block
   title ApplicationClient.java borderStyle solid
   package appclient; import java.io.BufferedReader; import java.io.InputStreamReader; import java.util.Properties; import ejb.CountryCapital; import javax.naming.Context; import javax.naming.InitialContext; public class ApplicationClient { public static void main(String [] args) { String capital=new String(); try{ Properties prop=new Properties(); prop.put(Context.INITIAL_CONTEXT_FACTORY, "org.apache.openejb.client.RemoteInitialContextFactory"); prop.put("java.naming.provider.url", "ejbd://localhost:4201"); Context context = new InitialContext(prop); CountryCapital myejb = (CountryCapital)context.lookup("CountryCapitalBeanRemote"); System.out.println("Give the name of a country"); BufferedReader in= new BufferedReader(new InputStreamReader(System.in)); String str=""; str=in.readLine(); capital=myejb.capitalName("str"); System.out.println(capital); } catch(Exception e) { e.printStackTrace(); } } }

   
   Let us try to understand following code snippet
   

   Code Block
   title CodeSnippet borderStyle solid
   Properties prop=new Properties(); prop.put(Context.INITIAL_CONTEXT_FACTORY, "org.apache.openejb.client.RemoteInitialContextFactory"); prop.put("java.naming.provider.url", "ejbd://localhost:4201"); Context context = new InitialContext(prop); CountryCapital myejb =(CountryCapital)context.lookup("CountryCapitalBeanRemote");

   
   

   Info
   title Useful Information
   The above code suggests that which InitialContextFactory to be used to create the InitialContext. Here we are using org.apache.openejb.client.RemoteInitialContextFactory to create the InitialContext. In this case as the EJB server is the naming service provider and has naming service runnning at Port 4201. So we need to specify the location of the EJB server. In this case it is ejbd://localhost:4201. Once this is done we have the context that provides us the ability to lookup and get objects.

   
   

   Tip
   title Why is the lookup name CountryCapitalBeanRemote?? :(
   This will be discussed in deploy and run section.

9. Next step is to add org.apache.openejb.client.RemoteInitialContextFactory Class to the build path. This is because the application client needs this Class to create the InitialContext as explained above.
10. Right click on ApplicationClient project under project explorer. Select Properties.
    
    
    
    
    
    
11. Select Java Build Path. Under Java Build Path select Libraries-> Add External JARs.
    
    
    
    
    
    
12. Browse to <GERONIMO_HOME>\repository\org\apache\openejb\openejb-client\3.0-beta-2 and Select the jar openejb-client-3.0-beta-2.jar. Select Ok.

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Sample Input1: India





Sample Input2: China





Sample Input3: United States Of America





Sample Input4: France

Download ApplicationClient.java
Downlaod SimpleEJB