For the relationship between the two in J2EE, it suddenly felt that it was not clear. Basic knowledge is starting from such a problem: EAR includes both EJB and Web, the web module has the dependence on the EJB module. There are some global configuration parameters to use two modules, which are previously placed in the form of a Util Class of the EJB module, which is initialized when defined, both of which can be directly accessed. Such a web module regards the JAR of the EJB module as an ordinary lib. Now these Static Field needs to initialize it according to some external configuration parameters. This brings a problem with a web module and an EJB module. And the Cluster may be involved in the future.
Suddenly discovered that many concepts are unclear: WEB can access the EJB module Class Class? In Cluster mode, is the web module always be with the EJB module? How will it be REMOTE? How is the so-called distribution of distribution, blurred the EJB module may access the group web module? Can the EJB module use static? Can you use Singleton? Web module deployment descriptor has a global parameter, all servlets have access to the EJB module? There is also a Web module and the EJB module startup order. I want to check what other restrictions in the EJB program, there is no way, and many of the information is not mentioned. "Mastering EJB2" seems to answer some questions, but not complete. Sun's website should have, but I don't know what keyword search.
