今天新下载了mysql-5.1.19还下了一个mysql-connector-java-5.1.0（都是mysql.com最新提供的），但是最简单的连库操作都不行了，鼓捣一晚上了，请大家出出主意吧，是哪里的问题呢？报错信息如下：
description The server encountered an internal error () that prevented it from fulfilling this request.
exception
org.apache.jasper.JasperException: org/aspectj/lang/Signature
org.apache.jasper.servlet.JspServletWrapper.handleJspException(JspServletWrapper.java:476)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:371)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:315)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:265)
javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
root cause
javax.servlet.ServletException: org/aspectj/lang/Signature
org.apache.jasper.runtime.PageContextImpl.doHandlePageException(PageContextImpl.java:846)
org.apache.jasper.runtime.PageContextImpl.handlePageException(PageContextImpl.java:779)
org.apache.jsp.web.sqldemo_jsp._jspService(sqldemo_jsp.java:79)
org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:98)
javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:328)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:315)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:265)
javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
root cause
java.lang.NoClassDefFoundError: org/aspectj/lang/Signature
java.lang.Class.forName0(Native Method)
java.lang.Class.forName(Unknown Source)
org.apache.jsp.web.sqldemo_jsp._jspService(sqldemo_jsp.java:62)
org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:98)
javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:328)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:315)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:265)
javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
note The full stack trace of the root cause is available in the Apache Tomcat/5.5.23 logs.
程序清单：
<%@page contentType= "text/html; charset=gb2312 "%>
<%@page language= "java "%>
<%@page import= "com.mysql.jdbc.Driver.* "%>
<%@page import= "java.sql.* "%>
<html>
<head>
<title> sqldemo </title>
</head>
<%!Connection con;%>
<%!Statement stmt;%>
<%!ResultSet rs;%>
<body bgcolor= "#ffffff ">
<%
Class.forName( "com.mysql.jdbc.Driver ");
con = DriverManager.getConnection( "jdbc:mysql://127.0.0.1:3306/demo?user=root&password=123 ");
String sql = "select * from flower ";
stmt = con.createStatement();
rs = stmt.executeQuery(sql);
rs.next();
int id = rs.getInt(1);
out.print( " " + id);
%>
</body>
</html>
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