新手上路，江湖救急，牛人帮帮忙呀
我在浏览器里运行signup.jsp就会报一下错误：（看得我一头雾水）
org.apache.jasper.JasperException:   Exception   in   JSP:   /signup.jsp:61

58:   prof.setUserid(signIn.getUserid());
59:   //prof根据输入的参数userid，查询该用户数据库中其他数据，并保存在

60:   //prof相关变量中
61:   if(signIn.signIn()&&prof.select()){
62:  
63:   %>
64:  


Stacktrace:
org.apache.jasper.servlet.JspServletWrapper.handleJspException(JspServletWrapper.java:467)
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:   Profile.update()null
org.apache.jasper.runtime.PageContextImpl.doHandlePageException(PageContextImpl.java:846)
org.apache.jasper.runtime.PageContextImpl.handlePageException(PageContextImpl.java:779)
org.apache.jsp.signup_jsp._jspService(signup_jsp.java:260)
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.Exception:   Profile.update()null
com.jdon.simpleregister.Profile.select(Profile.java:215)
org.apache.jsp.signup_jsp._jspService(signup_jsp.java:149)
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.


signup.jsp源码

<%@   page   language= "java "   pageEncoding= "UTF-8 "%>
<jsp:useBean   id= "signIn "   scope= "session "   class= "com.jdon.simpleregister.SignIn "/>
<jsp:useBean   id= "prof "   scope= "page "   class= "com.jdon.simpleregister.Profile "/>
<jsp:setProperty   name= "prof "   property= "* "/>

<%@   include   file= "head.html "%>

<%
//如果提交的是新增动作
if(request.getParameter( "add ")!=null){
//并且现有数据库这个email没有存在
if(prof.EmailExist()){

%>

<jsp:include   page= "error.jsp?error_info=null=email已经存在   请重新调换一个！ "   flush= "true "/>