我的tomcat 是5.5.20 jdk是1.6的 大家帮帮我啊　　数据库是mssql　server！！　谢谢
　　


HTTP Status 500 - 

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type Exception report

message 

description The server encountered an internal error () that prevented it from fulfilling this request.

exception 

org.apache.jasper.JasperException: Exception in JSP: /user_add_image.jsp:13

10:     <%
11:         String s_Rand_1 = (String)session.getAttribute("rand");
12:         String s_Rand_2 = request.getParameter("Rand");
13:         if (s_Rand_1.equals(s_Rand_2)) 
14:         {    
15:             String strSql="";
16:             String database_username="sa";


Stacktrace:
    org.apache.jasper.servlet.JspServletWrapper.handleJspException(JspServletWrapper.java:506)
    org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:395)
    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.NullPointerException
    org.apache.jsp.user_005fadd_005fimage_jsp._jspService(user_005fadd_005fimage_jsp.java:56)
    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.


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Apache Tomcat/5.5.20