java - HTTP 状态 500 - org.apache.jasper.JasperException : java. lang.NullPointerException

Question

我在生产服务器上部署了我的项目并收到以下错误。

这是一个实时项目，所以在出现错误后我将其替换为运行良好但现在也抛出相同错误的先前版本。请告诉我可能是什么问题？

错误:

HTTP Status 500 - org.apache.jasper.JasperException: java.lang.NullPointerException

--------------------------------------------------------------------------------

type Exception report

message org.apache.jasper.JasperException: java.lang.NullPointerException

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

exception 

org.apache.jasper.JasperException: org.apache.jasper.JasperException: java.lang.NullPointerException
    org.apache.jasper.servlet.JspServletWrapper.handleJspException(JspServletWrapper.java:502)
    org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:412)
    org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:313)
    org.apache.jasper.servlet.JspServlet.service(JspServlet.java:260)
    javax.servlet.http.HttpServlet.service(HttpServlet.java:717)


root cause 

org.apache.jasper.JasperException: java.lang.NullPointerException
    org.apache.jasper.servlet.JspServletWrapper.handleJspException(JspServletWrapper.java:502)
    org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:430)
    org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:313)
    org.apache.jasper.servlet.JspServlet.service(JspServlet.java:260)
    javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
    org.apache.jasper.runtime.PageContextImpl.doForward(PageContextImpl.java:709)
    org.apache.jasper.runtime.PageContextImpl.forward(PageContextImpl.java:680)
    org.apache.jasper.runtime.PageContextImpl.doHandlePageException(PageContextImpl.java:821)
    org.apache.jasper.runtime.PageContextImpl.handlePageException(PageContextImpl.java:794)
    org.apache.jsp.LPSSuppIndex_jsp._jspService(LPSSuppIndex_jsp.java:393)
    org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
    javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
    org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:388)
    org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:313)
    org.apache.jasper.servlet.JspServlet.service(JspServlet.java:260)
    javax.servlet.http.HttpServlet.service(HttpServlet.java:717)


root cause 

java.lang.NullPointerException
    org.apache.jsp.error_jsp._jspService(error_jsp.java:124)
    org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
    javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
    org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:388)
    org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:313)
    org.apache.jasper.servlet.JspServlet.service(JspServlet.java:260)
    javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
    org.apache.jasper.runtime.PageContextImpl.doForward(PageContextImpl.java:709)
    org.apache.jasper.runtime.PageContextImpl.forward(PageContextImpl.java:680)
    org.apache.jasper.runtime.PageContextImpl.doHandlePageException(PageContextImpl.java:821)
    org.apache.jasper.runtime.PageContextImpl.handlePageException(PageContextImpl.java:794)
    org.apache.jsp.LPSSuppIndex_jsp._jspService(LPSSuppIndex_jsp.java:393)
    org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
    javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
    org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:388)
    org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:313)
    org.apache.jasper.servlet.JspServlet.service(JspServlet.java:260)
    javax.servlet.http.HttpServlet.service(HttpServlet.java:717)


note The full stack trace of the root cause is available in the Apache Tomcat/6.0.36 logs.


--------------------------------------------------------------------------------

Apache Tomcat/6.0.36

索引页面.jsp:

<%@ page errorPage="error.jsp"%>
<%@ page import="java.util.*" %>
<%@ page import = "jdbc.RetrieveLangList,lang.MessageGetter" %>
<%!
    HashMap<String, String> langListMap = new HashMap<String, String>();
%>
<%
        //Retrieving language MAP
        RetrieveLangList objList = new RetrieveLangList();
        langListMap = objList.LangList();
        Set s = langListMap.entrySet(); // Get hashmap in Set interface to get key and value
        Iterator it = s.iterator(); // Move next key and value of HashMap by iterator

        String suppLang = "en_US";
        suppLang = request.getParameter("suppLanguage");
        if (suppLang == null || suppLang.equalsIgnoreCase(""))
            suppLang = "en_US";
%>
<html>
<HEAD>
<TITLE> Welcome to  </TITLE>
<link rel="SHORTCUT ICON" href="image/H.ico"/>
<LINK href="image/css/Rcontent.css" type="text/css" rel="stylesheet">
</HEAD>
<script language="JavaScript">
function loadPage(list)
{
  location.href=list.options[list.selectedIndex].value;
}
</script>
<SCRIPT language="Javascript">
    function ValidateForm()
    {
    //Supplier Number Validation
    var supp_number =document.loginForm.uname;

    if((supp_number.value=="su")||(supp_number.value=="SU"))
        {
            return true;
        }

    var stripped = supp_number.value.replace(/[\(\)\.\-\ ]/g, ''); 
    if((supp_number.value==null)||(supp_number.value==""))
        {
        alert("<%=MessageGetter.getMessage("lang.MessagesBundle", suppLang, "Enter_User_ID")%>");
        supp_number.focus();
        return false;
        }
    else if (isNaN(parseInt(stripped))) {
        alert("<%=MessageGetter.getMessage("lang.MessagesBundle", suppLang, "Invalid_User_ID")%>");
        supp_number.focus();
        return false;
         }

        //Password Validation
        var supp_pass =document.loginForm.pass;
    if((supp_pass.value==null)||(supp_pass.value==""))
        {
        alert("<%=MessageGetter.getMessage("lang.MessagesBundle", suppLang, "Enter_Password")%>");
        //alert("Please Enter Password");
        supp_pass.focus();
        return false;
        }
    return true;
    }
</SCRIPT>
<BODY bgcolor="#C7CACF">
<center>
<table border = "0" bordercolor = "black" style="background-image:url('image/backgroundIndex.jpg');background-repeat:no-repeat" width="1000" HEIGHT = "700" >
<tr height = "60">
    <td>&nbsp;</td>
    <td>&nbsp;</td>
    <td colspan="2">
    <form name="form1" >
    <TABLE border="0" width = "610">
    <TR>
       <td width="300" align="right" height="40">
            <select name="file" size="1" onchange="loadPage(this.form.elements[0])" target="_parent._top"  onmouseclick="this.focus()" style="background-color: #ffffff;width:150px;"> <!-- This is language selection box -->
            <%
            while (it.hasNext())
            {
                Map.Entry m = (Map.Entry) it.next(); // key=value separator this by Map.Entry to get key and value
                //System.out.println("value : "+m.getValue()+" key : "+m.getKey());
                if(suppLang.equals(m.getKey()))
                {
            %>
            <option value="LPSSuppIndex.jsp?suppLanguage=<%= m.getKey()%>" selected="selected"><%= m.getValue()%></option>
            <%
                }
                else
                {
            %>
            <option value="LPSSuppIndex.jsp?suppLanguage=<%= m.getKey()%>"><%= m.getValue()%></option>
            <%
                }
            }
            %>
            </select>
         </td>
         <td width = "300px" align="right"><a HREF="mailto:?subject=<%=MessageGetter.getMessage("lang.MessagesBundle", suppLang, "sub_contact")%>&body=<%=MessageGetter.getMessage("lang.MessagesBundle", suppLang, "body_line1_contact")%>, %0D%0D%0D<%=MessageGetter.getMessage("lang.MessagesBundle", suppLang, "body_line2_contact")%>, %0D%0D%0D<%=MessageGetter.getMessage("lang.MessagesBundle", suppLang, "body_line3_contact")%>%0D%0D%0D"><font color="#73767B" size="2"><%=MessageGetter.getMessage("lang.MessagesBundle", suppLang, "contact")%></font></a><font color="#73767B"><B> |</B></font><a href="http://www..com/en/service/imprint-legal-issues.html"><font color="#73767B" size="2"> <%=MessageGetter.getMessage("lang.MessagesBundle", suppLang, "imprint_legel_issue")%></font></a><font color="#73767B"><B> | </B></font><a href="http://www..com/en/service/sitemap.html"><font color="#73767B" size="2"><%=MessageGetter.getMessage("lang.MessagesBundle", suppLang, "sitemap")%></font></a></td>
    </TR>
    <TR height="12px">
        <TD colspan="2">&nbsp;</TD>
    </TR>
    </TABLE>
    </form>
    </td>
</tr>

<tr>
     <td height = "240px" valign="top">
        <TABLE border="0" width = "195">
        <TR>
            <TD height="40" width="155" align="left"><div style="position:relative;left: 20px;"><a href="LPSSuppIndex.jsp"><font color="#73767B" size="3"><%=MessageGetter.getMessage("lang.MessagesBundle", suppLang, "home")%></font></a></div></TD>
        </TR>
        <TR>
            <TD height="37" align="left"><div style="position:relative;left: 20px;"><A HREF="mailto:er_Admin@de..com?subject=<%=MessageGetter.getMessage("lang.MessagesBundle", suppLang, "sub_contact")%>&body=<%=MessageGetter.getMessage("lang.MessagesBundle", suppLang, "body_line1_contact")%>, %0D%0D%0D<%=MessageGetter.getMessage("lang.MessagesBundle", suppLang, "body_line2_contact")%>, %0D%0D%0D<%=MessageGetter.getMessage("lang.MessagesBundle", suppLang, "body_line3_contact")%>%0D%0D%0D"><font color="#73767B"><%=MessageGetter.getMessage("lang.MessagesBundle", suppLang, "contact")%></font></a></div></TD>
        </TR>
        <TR>
            <TD height="35" align="left"><div style="position:relative;left: 20px;"><a href="LPSSuppIndex.jsp"><font color="#73767B" size="3"><%=MessageGetter.getMessage("lang.MessagesBundle", suppLang, "log_in")%></font></a></div></TD>
        </TR>
        <TR>
            <TD height="34" align="left">&nbsp;&nbsp;&nbsp;<a href="http://wwwcom"><font color="white" style="font-family:Arial, Helvetica, sans-serif;font-size: 10pt; font-weight: bold"><%=MessageGetter.getMessage("lang.MessagesBundle", suppLang, "tportal")%></font></a></TD>
        </TR>
        <TR>
            <TD height = "32" align="center">&nbsp;</TD>
        </TR>
        <TR>
            <TD height = "43px" colspan="2" align="center">&nbsp;</TD>
        </TR>

        </TABLE>
    </td>

    <td colspan="2">&nbsp;</td>
    <td rowspan="3" valign="top">
        <table border="0px" >
            <tr height="139px"><td>&nbsp;</td><td>&nbsp;</td></tr>
            <tr height="431px">
                <td valign="top" width="8px"><div class="vertical-line" style="position:relative;left:27px;top:0px;"></div></td>
                <td valign="top">
                    <!-- START RIGHT CONTENT  -->

                    <DIV class="cntr_cnt_gradbox" style="position: relative;left: 15px;top: -5px;">
                    <DIV class="cntr_head"><font size="2%"><%=MessageGetter.getMessage("lang.MessagesBundle", suppLang, "PDF_download")%>&nbsp;</font></DIV>
                    <DIV class="cntr_cnt_gradbox_inner">
                        <DIV class="cntr_frame" style="height: 60px;">
                            <DIV style="FLOAT: left;height: 50px;" >
                                <IMG src="image/PDF_Thumbnail_50x50.gif" border="0">
                            </DIV>
                            <DIV class="cntr_dl_cnt" style="MARGIN-LEFT: 55px;">
                                <A class="cntr_lnk" href="PDF/User Maner_EN.pdf" target="_blank"><font color="#73767B" size="2%"><%=MessageGetter.getMessage("lang.MessagesBundle", suppLang, "manual_en")%></font></A>
                            </DIV>&nbsp;
                            <BR class="clr">
                        </DIV>
                        <BR class="clr">
                        <DIV class="cntr_frame" style="height: 60px;">
                            <DIV style="FLOAT: left;height: 50px;" >
                                <IMG src="image/PDF_Thumbnail_50x50.gif" border="0">
                            </DIV>
                            <DIV class="cntr_dl_cnt" style="MARGIN-LEFT: 55px;">
                                <A class="cntr_lnk" href="PDF/Benutzerhl Printer_DE.pdf" target="_blank"><font color="#73767B" size="2%"><%=MessageGetter.getMessage("lang.MessagesBundle", suppLang, "manual_de")%></font></A>
                            </DIV>&nbsp;
                            <BR class="clr">
                        </DIV>
                        <BR class="clr">
                        <DIV class="cntr_frame" style="height: 60px;">
                            <DIV style="FLOAT: left;height: 50px;" >
                                <IMG src="image/PDF_Thumbnail_50x50.gif" border="0">
                            </DIV>
                            <DIV class="cntr_dl_cnt" style="MARGIN-LEFT: 55px;">
                                <A class="cntr_lnk" href="PDF/Print_Specification.pdf" target="_blank" title="<%=MessageGetter.getMessage("lang.MessagesBundle", suppLang, "printHelp_tip")%>"><font color="#73767B" size="2%"><%=MessageGetter.getMessage("lang.MessagesBundle", suppLang, "printHelp")%></font></A>
                            </DIV>
                            <BR class="clr">
                        </DIV>
                        <DIV class="cntr_frame1" style="height: 30px;">
                             <div style="margin-left: 30px;"> <A class="cntr_lnk" href="PDF/quick_guide_en.pdf" target="_blank"><font color="#73767B" size="2%"><%=MessageGetter.getMessage("lang.MessagesBundle", suppLang, "one_point_lessons")%> - EN</font></A></div>
                        </DIV>

                        <DIV class="cntr_frame1" style="height: 30px;">
                             <div style="margin-left: 30px;"> <A class="cntr_lnk" href="PDF/quick_guide_de.pdf" target="_blank"><font color="#73767B" size="2%"><%=MessageGetter.getMessage("lang.MessagesBundle", suppLang, "one_point_lessons")%> - DE</font></A></div>
                        </DIV>
                        <DIV style="height: 30px;vertical-align: middle;">
                             <div style="margin-left: 30px;"> <A class="cntr_lnk" href="PDF/FAQ.pdf" target="_blank"><font color="#73767B" size="2%">FAQ</font></A></div>
                        </DIV>
                        </DIV>
                    </DIV>
                </td>
            </tr>
        </table>
    </td>
</tr>

<tr height = "210">
    <td>&nbsp;</td>
     <td>&nbsp;</td>
     <td>
     <form method="post" name="loginForm" action="./loginServlet" onsubmit="return ValidateForm()">
     <input type="hidden" name="selectedLang" value="<%=suppLang%>" >
     <TABLE border="0" bordercolor="black" width="370">
     <tr><td rowspan="6" width = "30">&nbsp;</td></tr>

     <TR height="45">
        <td width="110" ><%=MessageGetter.getMessage("lang.MessagesBundle", suppLang, "user_id")%> : </td><!-- This is Supplier Number(User ID) entry field. -->
     <td width="230" align="center"><input type="text" size="25" name="uname" style="border-color: #529DFA;" maxlength="10"></td>
     </TR>
     <TR>
     <td height="45"><%=MessageGetter.getMessage("lang.MessagesBundle", suppLang, "Password")%> : </td><!-- This is Password entry field. -->
      <td align="center"><input type="password" size="25" name="pass" style="border-color: #529DFA;"></td>
     </TR>
     <TR height="40">
     <td>&nbsp;</td>
     <td align ="center" height="40"><A HREF="mailto_Printer_Admin@de.h.com?subject=<%=MessageGetter.getMessage("lang.MessagesBundle", suppLang, "sub_forget_password")%>&body=<%=MessageGetter.getMessage("lang.MessagesBundle", suppLang, "body_line1_forget_password")%>, %0D%0D%0D<%=MessageGetter.getMessage("lang.MessagesBundle", suppLang, "body_line2_forget_password")%>%0D%0D%0D"><%=MessageGetter.getMessage("lang.MessagesBundle", suppLang, "forget_password")%></A>
    </td>
     </TR>
     <TR>   
     <td height="40" align="right"><input type="Submit" value="<%=MessageGetter.getMessage("lang.MessagesBundle", suppLang, "log_in")%>" /> </td>
     <td align="center"><input type="button" onClick="location.href='register/suppRegistration.jsp?selectedLang=<%=suppLang%>'" value="<%=MessageGetter.getMessage("lang.MessagesBundle", suppLang, "new_user")%>" /></td>
     </TR>
     </TABLE></form>
     </td>
</tr>

<tr height = "114">
    <td>&nbsp;</td>
    <td>&nbsp;</td>
    <td>&nbsp;</td>
</tr>

<tr>
    <td width = "200">&nbsp;</td>
    <td width="170">&nbsp;</td>
    <td width="380">&nbsp;</td>
    <td width="230" align="center">&nbsp;</td>
</tr>
</table>
</center>
</BODY>
</HTML>

Answer 1

在 Tomcat 中，将为应用程序中的每个 jsp 文件创建一个 .java 和 .class 文件，可以从以下路径找到相同的文件，Apache-Tomcat\work\Catalina\localhost\'ApplicationName'\org\apache\jsp\index_jsp.java

在您的例子中，jsp 名称是 error.jsp，因此路径应该如下所示Apache-Tomcat\work\Catalina\localhost\'ApplicationName'\org\apache\jsp\error_jsp.java 在第 124 行你试图访问一个空对象，这会导致空指针异常。