1. Enterprise Java Beans(EJB) With EJBs, you can develop building blocks ‘ejb components ’ – that u and someone else can assemble and reassemble into different applications. For example , you might create a customer bean that represents a customer in database. You can use that Customer bean in an accouting program, an e-commerce shopping cart and a tech support application. One beauty of EJBs is that you take code reuse to a whole new level, instead of just code it reuses whole functionality and allows you modify that way bean behaves at runtime with touching its java code. 06/22/10 JavaTruths.com:A Portal for all java related stuff!!!
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14. Put the Bean, the interface and the DD into ejb-jar file META-INF EJB-JAR.XML MYPACKAGE AdvcieBean.class AdviceHome.class Advice.class MYEJB.JAR ejb-jar.xml must be in a directory named META-INF 06/22/10 JavaTruths.com:A Portal for all java related stuff!!!
15. Deploy the bean into the server,using the tools provided by the server vendor 06/22/10 JavaTruths.com:A Portal for all java related stuff!!!
19. EJB uses RMI 06/22/10 JavaTruths.com:A Portal for all java related stuff!!!
20. How EJB uses RMI 06/22/10 JavaTruths.com:A Portal for all java related stuff!!!
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25. How EJB really Works? 06/22/10 JavaTruths.com:A Portal for all java related stuff!!!
26. How EJB really Works? 06/22/10 JavaTruths.com:A Portal for all java related stuff!!!
27. How EJB really Works? 06/22/10 JavaTruths.com:A Portal for all java related stuff!!!
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49. Container callbacks invocation 06/22/10 JavaTruths.com:A Portal for all java related stuff!!! Does not Exist Method ready Passivated setSessionContext() ejbCreate() ejbPassivate() ejbActivate() ejbRemove() or timeout Bean throw system exception timeout
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53. Use sessioncontext for 06/22/10 JavaTruths.com:A Portal for all java related stuff!!! setSessionContext() ejbCreate() Within business method Use your SessionContext for: Get a reference to your home Get a reference to home Get a reference to home Get a reference to your EJB Object Get a reference to your EJB Object Get security info about the client Get security info about the client Get a transaction reference and call methods on it(BMT Beans) For a transaction to rollback(CMT beans) Find out if the transaction has already been set to rollback(CMT beans) Get a transaction reference and call methods on it (BMT beans) Access : Your special JNDI Environment Your special JNDI Env. Your special JNDI Env. Another beans methods Another beans methods A resource manager(like a DB) A resource manager(like a DB)
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