问题大概是这样的:
首页index.jsp调用写好的类方法,实现查询,但总是报错,关键信息如下:
index.jsp:
<%@page language="java" contentType="text/html;charset=utf-8"%>
<%@page import="java.sql.*"%>
<%@page import="java.util.*"%>
<%@page import="MySql.*"%>
<%
……
ResultSet result=DataManager.Query(sql);
……
%>
DataManager文件结构如下图:
运行报错如下:
org.apache.jasper.JasperException: MySql.DataManager.Query(Ljava/lang/String;)Ljava/sql/ResultSet;
org.apache.jasper.servlet.JspServletWrapper.handleJspException(JspServletWrapper.java:512)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:377)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:314)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:264)
javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
root cause
javax.servlet.ServletException: MySql.DataManager.Query(Ljava/lang/String;)Ljava/sql/ResultSet;
org.apache.jasper.runtime.PageContextImpl.doHandlePageException(PageContextImpl.java:843)
org.apache.jasper.runtime.PageContextImpl.handlePageException(PageContextImpl.java:776)
org.apache.jsp.index_jsp._jspService(index_jsp.java:347)
org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:97)
javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:334)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:314)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:264)
javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
root cause
java.lang.NoSuchMethodError: MySql.DataManager.Query(Ljava/lang/String;)Ljava/sql/ResultSet;
org.apache.jsp.index_jsp._jspService(index_jsp.java:55)
org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:97)
javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:334)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:314)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:264)
javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
note The full stack trace of the root cause is available in the Apache Tomcat/5.5.20 logs.
请多多指教,不胜感激。