where does ejb server comes into???i mean therez this web server then one deep down we need application servers for ejb containers....bt since application servers can do the work of web servers only having a application server like jboss or glassfish serves the purpose...now where does the ejb server fits into???inside ejb container???inside or outside application servers?i am confused
Well, it's pretty simple: a web container (such as Jetty or Tomcat) do provide an environment to run web components, such as Servlets and JSPs. But they do not provide infrastructure and do not offer some APIs, such as security, transactionality, Java Mail, etc. That's where application servers come in. An application server (such as JBoss or Glassfish) have embedded web containers and provide all the infrastructure necessary to build big enterprise applications.
Normally, application servers are "heavyweight", that is, they aren't very fast (or slow, if you will) when starting, for instance. Spring's first purpose was to be an alternative to these heavyweight containers, and this way, you could benefit of the speed of the web containers and still have all the infrastructure. So, if you want to build a real enterprise application and use a webcontainer, Spring is the way to go.
@Roberto thanks for your reply.....okay i get it Spring is the upcoming or almost the one technology that is making d buzz...but i dnot understand where actually is this EJB Server working???insider application server???within component?where exactly....??
Oh, right. The EJB server is the program that runs inside the application server and allows EJB-based applications to be deployed and run. The application server is the entire infrastructure. Please take a look here for more details about application servers.
Joined: Jun 09, 2011
wow....its like super complex for those who actually made it???a nested server sort of concept then???as you said within the application server runs the EJB server...though both the servers have different functionality.