So that the readers of this book on learning the real and practical technology,...

代码说明：

方面，使读者通过对本书的学习，学到真正实用的技术，另一方面，为引入J2EE技术打下良好的基础-So that the readers of this book on learning the real and practical technology, on the other hand, for the introduction of J2EE technology and lay a good foundation