When I just entered the company, the project manager asked me: "Do you want to do a reception or a background?" I didn't think of thinking "background". So started to learn EJB with the project's backbone. For EJB this, some of themselves, Of course, it is mainly some of the idea of individuals. It is not technically 咚. When the project group often hears someone says that ejb This thing is not good, how is it no future. Their point of view (the only point of view) is EJB is too efficient. I have not done what tests, I don't have to judge their views. However, I am convinced that there is no punishment, that is, the more fierce, the ability is often more trouble. I have an experience in this project, one of them. It's a bug king.
Let's talk about the problems they say (not specific to technical and performance test here).
I think it is entirely on the user. Therefore, I think about performance from the user's perspective. We do office automation, the technology used is EJB STRUCTS JBOSS TOMCAT. For our products When the system is just running, the open page is indeed slow (similar to the first run of JSP is relatively slow), but the speed is still satisfactory. Of course, you may think that hardware makes it. So I tell you, we It is 1W MONEY IBM server, 1G memory, CPU is less than 3G. If you think that such a machine is very 8 wrong, then I tell you, the machine is better than this movie is best not to run EJB. Oh, now Hibernate, many people take Hibernate to compare with EJB, indeed, I personally feel that Hibernate has had his income in request and running, but it can't mean that EJB can't do it. There is no data here, I think I am not an expert, there are also many related articles on the Internet. As I personally, the performance problem should still listen to the user's point of view, think from the perspective of the user.
Second, to say that the EJB is unhappy, then it is more complicated and cumbersome, what profile, interface, abstract class. When I wrote, I often make a dizzy turn, often leaking some things. I believe that as a user (although it is a programmer, but as sun, the programmer is the user) Write EJB is a painful thing. I heard that EJB3.0 has made a lot of improvements in the grammatism, just as SUN is now advocated It is to simplify the work of the programmer. First go to the technology, do not say, light simplify the grammat, EJB3.0 is already worthy of my expectation. Of course, simplified grammar will change some program habits, which is inevitable.
Third, I have seen the related hibernate example, admire his small clever (for performance, huh, my nerve reflection is slow, there is a bit numb). However, I think I should learn from EJB (I don't know if Hibernate has This feature, I only read the example, I don't know much about the advanced Hibernate app), there is a
Fourth, for JDK1.5, there are now many online information to be introduced. I think (I think of course, ^ _ ^) EJB3.0 will inevitably consider the factors of 1.5, the simple amount of EJB3.0 is also attached to JDK1.5 So here, JDK1.5 is also mentioned here, not to take into account the perspective of technology. I have seen some sings about JDK1.5, don't say anything else, I think Sun is "simple" proposed by Java. One of the ideas a bit apart. One of the advantages of Java is that its grammar is simple and easy to learn, and 1.5 has added its difficulty in grammar (it is not complicated than other languages, but it is indeed complicated with it. It is a lot of lazy people, and I believe that all the programmers have lazy commonality. (Oh, a kind of cheap and bought a feeling) This probably the so-called fish and bear's paw can not be more .
Summary in a sentence, "existence is the truth".!
