Introduction - If you have any usage issues, please Google them yourself
In this paper, five aspects of J2EE have been a more comprehensive introduction. Speaking from the concept of J2EE, to its advantage, to the typical four-J2EE model, and its frame structure, and finally the 13 kinds of J2EE core technology of a profile. This article on J2EE categories of services, components, levels, and containers, API has done a more detailed introduction, I believe after reading this article, readers will have a J2EE a clearer understanding.