《J2EE企业级应用开发》一书的配套源代码，涵盖XML编程，Servlet，JSP，自定义标签库开发，JSTL，EL，EJB，Web Services，JAX－RPC等内容。-"J2EE Enterprise Application Development," a book supporting source code, covering XML Programming, Servlet and JSP-defined labels for development, scr

JSP，跳转到不同的JSP界面，同时使用标签检查该用户是否已登录，已登录显示余额界面，未登录的显示登录界面-JSP, jump to a different JSP interface, use the label to check whether the user is logged on, logged shows the balance interface unregistered display login screen