Enterprise java beans have three types of beans
(1)Session bean
session bean is subdivided into two
a.stateless session bean:It works on a single request paradigm while statefull bean works on multiple request paradigm.Single request paradigm does not required the state.For example:Credit card verification is done within one states like check only validity.
a.statefull session bean:It is used to services business process which uses multiple transaction or multiple requests.For Example:With draw money in bank will take multiple states like check balance, permitted with admin if more, signed matched, money provider etc.
(2)Entity Bean
Entity bean is subdivided into two
a.BMP:BMP stands for bean managed persistent.This is entity bean where developer has to be write the code manually for transferring the data from database to application server.But developer need not worry about coding for transferring.
b.CMP:CMP stands for container managed persistent.In BMP entity bean for transferring data from database to server there will be a code that is managed by CMP.
(3)Message driven bean