從“Spring與EJB3.0的比較”一文開始，我對EJB3.0關注也更多了一些，關于Spring與EJB3.0的比較詳見http://www.onjava.com/lpt/a/5996。我對該文的翻譯為http://www.aygfsteel.com/Files/ablix/EJB.rar，后來發(fā)現(xiàn)在matrix.org同樣存在該文的翻譯http://www.matrix.org.cn/resource/article/43/43718_Spring_EJB.html。
通過對Jboss EJB3.0及Oracle EJB3.0參考實現(xiàn)（GlassFish）的了解，覺得簡單的EJB3.0開發(fā)還算比較簡單。從“The Performance of EJB 3.0”一文（http://java.sys-con.com/read/131767_1.htm、http://www.jaoo.org/articles/ejb3perf.jsp）中發(fā)現(xiàn)，EJB 3.0的性能并不差。
文中首先指出EJB3.0規(guī)范非常簡單和強大，覺得性能會很差，因為簡單一般是要付出代價的。但經(jīng)過一系列的測試，表明EJB3.0的性能要比EJB2.1高很多，特別是在并發(fā)用戶較大時，EJB3.0的性能及用戶吞吐量甚至是EJB2.1的兩倍。
文中的最后結論如下：
Conclusion
Considering that we used only a developer's preview of EJB 3.0, we're very impressed with this specification - at least Oracle's implementation of it. As mentioned earlier, we're very attracted to the simplicity and power of EJB 3.0. The wonderful work done with annotations and the persistence, the ability to use POJOs, and the ability to test outside of the container are very attractive all by themselves. But now, with an implementation that equals or doubles the performance of EJB 2.1 (at least for our test cases), we can't wait for the final specification and formal release of EJB 3.0.