一个错误异常java.lang.NoSuchMethodError，没有这样的方法错误，不过你可别被它的这个名字给忽悠了，因为我明明是有这个方法的，按ALT+S里还有这个方法的智能提示。我觉得这个是TOMCAT的本身的问题，按CTRL+S保存会即时的编译一些代码，但是有时候会出现一些小BUG，想这样的错误关掉TOMCAT重新部署项目后再启动就OK了。

严重: Servlet.service() for servlet jsp threw exception
java.lang.NoSuchMethodError: bll.ProductBLL.Insert(Ldb/BeanBase;)I
 at org.apache.jsp.MyJsp_jsp._jspService(org.apache.jsp.MyJsp_jsp:69)
 at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:97)
 at javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
 at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:332)
 at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:314)
 at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:264)
 at javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
 at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:252)
 at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
 at appCode.CharacterEncodingFilter.doFilter(CharacterEncodingFilter.java:111)
 at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202)
 at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
 at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:213)
 at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:178)
 at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:126)
 at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:105)
 at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:107)
 at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:148)
 at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:869)
 at org.apache.coyote.http11.Http11BaseProtocol$Http11ConnectionHandler.processConnection(Http11BaseProtocol.java:667)
 at org.apache.tomcat.util.net.PoolTcpEndpoint.processSocket(PoolTcpEndpoint.java:527)
 at org.apache.tomcat.util.net.LeaderFollowerWorkerThread.runIt(LeaderFollowerWorkerThread.java:80)
 at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:684)
 at java.lang.Thread.run(Thread.java:595)