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LEARNINGS OF J2EE(04/10/2011)

J2EE Containers

  • Helps in separating the business logic and other mechanisms like Resource pooling , multi-threading and state management .
  • Before Deployment Any Component is to be assembled to the J2EE container.
  • Each assembly owns the settings for the container services like Security, Transaction management, JNDI, Remote Connectivity, etc.
  • JNDI lookup services provide a unified interface to multiple naming and directory services in the enterprise so that application components can access naming and directory services.
  • The J2EE remote connectivity model manages low-level communications between clients and enterprise beans. After an enterprise bean is created, a client invokes methods on it as if it were in the same virtual machine.
  • Having configurable environment it can behave differently on different environment.
  • Also provides some non-configurable services like data persistence, dB resource pooling, servlet lifecycle, Enterprise bean.


 

J2EE CONTAINER TYPES



 
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