Jboss EJB 3.0--stateless Beans

Jboss EJB 3.0



Stateless Beans







Calculator.java//Calculator interface: Add, subtract



Package Org.jboss.tutorial.stateless.bean;







public interface Calculator



{



int add (int x, int y);







int subtract (int x, int y);



}











Calculatorbean.java



Package Org.jboss.tutorial.stateless.bean;







Import javax.ejb.Stateless;







@Stateless//Mark Calculatorbean as stateless bean, implementation for local and remote interfaces



public class Calculatorbean implements Calculatorremote, calculatorlocal



{



public int Add (int x, int y)



{



return x + y;



}







public int subtract (int x, int y)



{



return x-y;



}



}











Calculatorlocal.java



Package Org.jboss.tutorial.stateless.bean;







Import javax.ejb.Local;







@Local//marked as local interface, inherited calculator interface



Public interface Calculatorlocal extends Calculator



{



}







Calculatorremote.java



Package Org.jboss.tutorial.stateless.bean;







Import Javax.ejb.Remote;







@Remote//marked as remote interface, inherited calculator interface



Public interface Calculatorremote extends Calculator



{



}







Client







Client.java



Package org.jboss.tutorial.stateless.client;







Import Org.jboss.tutorial.stateless.bean.Calculator;



Import Org.jboss.tutorial.stateless.bean.CalculatorRemote;







Import Javax.naming.InitialContext;







public class Client



{



public static void Main (string[] args) throws Exception



{



InitialContext CTX = new InitialContext ();



Find a remote interface



Calculator Calculator = (Calculator) ctx.lookup (CalculatorRemote.class.getName ());







System.out.println ("1 + 1 =" + Calculator.add (1, 1));



System.out.println ("1-1 =" + calculator.subtract (1, 1));



}



}































Simplified version ********************************







Statelessbean function can be achieved with only three programs.



Calculator.java



Package Org.jboss.tutorial.stateless.bean;







Import Javax.ejb.Remote;







@Remote//Directly mark calculator as a remote interface



public interface Calculator



{



int add (int x, int y);







int subtract (int x, int y);



}















Calculatorbean.java



Package Org.jboss.tutorial.stateless.bean;







Import javax.ejb.Stateless;







@Stateless



The public class Calculatorbean implements Calculator//here implements the Calculator interface



{



public int Add (int x, int y)



{



return x + y;



}







public int subtract (int x, int y)



{



return x-y;



}



}











Client:







Client.java



Package org.jboss.tutorial.stateless.client;







Import Org.jboss.tutorial.stateless.bean.Calculator;



Import Javax.naming.InitialContext;







public class Client



{



public static void Main (string[] args) throws Exception



{



InitialContext CTX = new InitialContext ();



Calculator Calculator = (Calculator) ctx.lookup (Calculator.class.getName ());



Just look for an interface that's marked as remote.



System.out.println ("1 + 1 =" + Calculator.add (1, 1));



System.out.println ("1-1 =" + calculator.subtract (1, 1));



}



}











Here attached log4j.properties inside Jboss-ejb-3.0_preview_5.zip No this is always showing a lack of appender







Log4j.properties



Log4j.appender.r=org.apache.log4j.rollingfileappender







Log4j.appender.r.file=record.log







Log4j.appender.r.layout=org.apache.log4j.patternlayout







Log4j.appender.r.layout.conversionpattern=%p%d{hh:mm:ss}%t%c{1}-%m%n







Log4j.appender.r.maxbackupindex=1







log4j.appender.r.maxfilesize=100kb







Log4j.appender.stdout.layout=org.apache.log4j.patternlayout







log4j.appender.stdout.layout.conversionpattern=%5p [%t] (%f:%l)-%m%n







Log4j.appender.stdout=org.apache.log4j.consoleappender







Log4j.rootlogger=stdout,r















Running: Reference installing.html



Under Windows



Open command Prompt cmd, to Jboss_home/bin



Run.bat–c All



With Ant



Just build and run.











Discuss:



The simplified version is to see the jboss-ejb-3.0_preview_5.zip inside the statefull source and rewrite, in the EJB SPE 3.0 said like to delete the home interface, I think the simplification of many interfaces more aspects, effective development of Java EE Application