HTTP 状态 500 - 处理 JSP 页面时发生异常

Question

如果我在 netbeans 上运行此应用程序，它可以正常工作而没有任何错误，但我想在不使用 netbeans 的情况下运行此 Web 应用程序（.war）。

我是 tomcat 的新手并开发了这个 web 应用程序，我安装了 tomcat、javaEE 6 和 glassfish、MY SQL 并配置了所有内容。一段时间后它的工作开始正常，它给出了这个错误，然后我不断刷新它再次工作，一段时间后它再次重复。

                                 OR

您有任何其他选项可以在不使用 netbeans 的情况下运行此 Web 应用程序 (.war)，我想向最终用户隐藏源代码。谁能帮帮我？

    type Exception report

message An exception occurred processing JSP page /KichenDisplay.jsp at line 177

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

exception

org.apache.jasper.JasperException: An exception occurred processing JSP page /KichenDisplay.jsp at line 177

174:                   
175: <%
176: Orders or=new Orders();
177: list=or.getData(activeid);
178: itr=list.iterator();
179: while(itr.hasNext()){
180: ActionForm af=(ActionForm) itr.next(); 


Stacktrace:
    org.apache.jasper.servlet.JspServletWrapper.handleJspException(JspServletWrapper.java:568)
    org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:470)
    org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:390)
    org.apache.jasper.servlet.JspServlet.service(JspServlet.java:334)
    javax.servlet.http.HttpServlet.service(HttpServlet.java:728)
    org.netbeans.modules.web.monitor.server.MonitorFilter.doFilter(MonitorFilter.java:393)

root cause

java.lang.NullPointerException
    com.manager.Orders.getData(Orders.java:31)
    org.apache.jsp.KichenDisplay_jsp._jspService(KichenDisplay_jsp.java:264)
    org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
    javax.servlet.http.HttpServlet.service(HttpServlet.java:728)
    org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:432)
    org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:390)
    org.apache.jasper.servlet.JspServlet.service(JspServlet.java:334)
    javax.servlet.http.HttpServlet.service(HttpServlet.java:728)
    org.netbeans.modules.web.monitor.server.MonitorFilter.doFilter(MonitorFilter.java:393)

note The full stack trace of the root cause is available in the Apache Tomcat/7.0.41 logs.
Apache Tomcat/7.0.41

Answer 1

这是我使用的源代码

Orders.java
/* * 要更改此许可标头，请在项目属性中选择许可标头。 * 要更改此模板文件，请选择工具 |模板 * 并在编辑器中打开模板。 */

package com.manager;

import com.manager.Forms.ActionForm;
import com.manager.util.DBConnection;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.logging.Level;
import java.util.logging.Logger;

/**
 *
 * @author krishna
 */
public class Orders {
    Connection con;
    PreparedStatement ps;
    ArrayList<ActionForm> list;
    public ArrayList<ActionForm> getData(String id) throws SQLException{
        DBConnection db=new DBConnection();
        con=db.getConn();
        list=new ArrayList<ActionForm>();
        ps=con.prepareStatement("select item,quantity,status,action,waction from orders where tableid="+id);
        ResultSet rs=ps.executeQuery();
        while(rs.next()){
        list.add(new ActionForm(rs.getString(1),rs.getString(2),rs.getString(3),rs.getString(4),rs.getString(5)));
        }
        return list;

    }
    public int getNotification(){

        int cnt=0;
        try {

            DBConnection db=new DBConnection();
            Connection con=db.getConn();
            PreparedStatement ps=con.prepareStatement("select count(distinct(tableid)) from orders where checkout=1");
            ResultSet rs=ps.executeQuery();
            if(rs.next()){
                cnt=rs.getInt(1);
            }
        } catch (SQLException ex) {
            Logger.getLogger(Orders.class.getName()).log(Level.SEVERE, null, ex);
            cnt=0;
        }
    finally{
        return cnt;
        }
    }
    public ArrayList getCheckedOut(){
        ArrayList list=new ArrayList();
    try{
    DBConnection db=new DBConnection();
    Connection con=db.getConn();
    PreparedStatement ps=con.prepareStatement("select distinct(tableid) from orders where checkout=1");
    ResultSet rs=ps.executeQuery();
    while(rs.next()){
    list.add(rs.getString(1));
    }
    }
        catch(Exception e){}
        finally{
        return list;
        }
    }
}

Kitchendisplay.java

<%-- 
    Document   : KichenDisplay
    Created on : Dec 2, 2013, 5:29:48 PM
    Author     : admin
--%>

<%@page import="com.manager.Forms.ActionForm"%>
<%@page import="com.manager.Orders"%>
<%@page import="com.manager.Forms.TableForm"%>
<%@page import="java.util.Iterator"%>
<%@page import="java.util.ArrayList"%>
<%@page import="com.manager.Tables"%>
<%@page contentType="text/html" pageEncoding="UTF-8"%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
   "http://www.w3.org/TR/html4/loose.dtd">

<html>
    <head>
        <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
        <meta http-equiv="Refresh" content="5">
        <title><%=getServletContext().getInitParameter("name")%></title>
        <link rel="stylesheet" type="text/css" href="css/notification.css" />
        <link href="css/modal.css" rel="stylesheet" type="text/css" />
        <link href="style.css" rel="stylesheet" type="text/css" />
        <link href="css/circles.css" rel="stylesheet" type="text/css" />
        <script src="js/jquery.js"></script>
        <link href="css/scroll.css" rel="stylesheet" type="text/css" />
<script src="js/getData.js"></script>

        <style>
            #circl{
                width: 52px;
                height: 52px;
                background:gray;
                -moz-border-radius: 500px;
                -webkit-border-radius: 500px;
                border-radius: 500px;

            }
            a{
                text-decoration: none;
            }
        </style>
    </head>

   <body background="images/bg2.png">
       <div id="circles"></div>
            <script>loadContent()</script>
<!---->

            <fieldset style="height:700">
        <img src="">


 <div style="background: url(images/top.png);width: 100%;height: 100px;margin-top: -20px">
            <br>
            <img src="images/Dg.png">
        </div>


         <table    style="background: url(images/tabb.png);width: 100%;height: 1px;margin-top: -40px">
             <tr>
              <%
                Orders o=new Orders();
                int c1=o.getNotification();
                %>
                 <td style="width:6%;text-align: center;font-size: 13px;text-align: center;margin-top: -40px"><b>
                     <a href="BillDesk.jsp" Style="color:white">BillDesk</a>

                            <div class="notification-container">
<!--    <i class="icon-globe"></i>-->
    <%if(c1!=0){%>
    <span class="notification-counter"><a href="#join_form"><%=c1%></a></span><%}%>
</div>
</b></td>
                 <td style="width:7%;background: url(images/sbt.png);font-size: 12px;text-align: center"><b>
                        <FONT COLOR=white><a href="KichenDisplay.jsp" Style="color:black">Kichen Display</a>
                    </FONT></b></td>
                  <td style="width:10%;font-size: 14px"><b><FONT COLOR=WHITE><a href="WaiterDisplay.jsp" Style="color:white">Waiter Display</a></FONT></b></td>
                  <td style="width:6%;font-size: 14px"><b><FONT COLOR=WHITE><a href="menu.jsp" Style="color:white">Menu</a></FONT></b></td>
                   <td style="width:8%;font-size: 14px"><b><FONT COLOR=WHITE><a href="transactions" Style="color:white">Transaction</a></FONT></b></td>
                    <td style="width:7%;font-size: 14px"><b><FONT COLOR=WHITE><a href="GetMenu.jsp" Style="color:white">Sync</a></FONT></b></td>
                     <td><b><FONT COLOR=WHITE><a href="Contact.jsp" Style="color:white;font-size: 15px">Contact Us</a></FONT></b></td>
            </tr>
        </table><br>
        <table>
    <tr>

        <td>
        <div style=color:lightslategray>
            Tables
        </div>

        <fieldset style="margin-left: 30px;background: white">
        <div style="margin-left: 5px;margin-left: 1px;background-image: url(images/tab.png);width: 350px;height: 400px">
             <table style="margin-left: 25px">
                <%
                int cnt=0,count=0;
                //String c=(String)(session.getAttribute("count")+"");
                //if( !c.equals("null") || c!="null" || !c.equals(null) || c!=null)
                   // cnt=Integer.parseInt(c);

    String activeid=request.getParameter("id");
    if(activeid==null)
        activeid="0";
    Tables t=new Tables();
    ArrayList list=t.getTables();
    Iterator itr=list.iterator();
    while(itr.hasNext()){
        out.println("<tr>");
        for(int i=0;i<5&&itr.hasNext();i++){
            TableForm tf=(TableForm)itr.next();
            String id=tf.getId();
            String ordered=tf.getOrdered();
            String color="gray";
            boolean f=false;
             String img="images/gray.png";
             String link="#";
            if(ordered.equals("1"))
            {
                color="green";
                f=true;
                link="KichenDisplay.jsp?id="+id;
                img="images/green.png";
                count++;
            }
            if(activeid.equals(id)){
                color="red";
                img="images/red.png";
            }
            session.setAttribute("count",count+"");

        %><td> 
            <a href="<%=link%>" style="text-decoration: none;">
            <div style="background:url(<%=img%>)" id="circl">


                <p style="width:40px;height: 1px;font-weight: bolder;text-align: center;margin-top: 15px;">
                <div style='margin-left: 25px;margin-top: 17px'><%=id%></div>
                    </p>

                 </div></a>
                        </td><%
        }
            //out.println(itr.next());
        out.println("</tr>");
    }

%>
                     </table>

        </div>

        </fieldset>
                     <%if(cnt!=count){
                         System.out.println("cnt:"+cnt+" count:"+count);
                         out.println("<embed height='0' width='0' src='css/s.mp3'/>");
                     }
                     else{
                        System.out.println("cnt:"+cnt+" count:"+count);
                     }%>
        </td>
        <td>                      <!--embed height="0" width="0" src="css/s.mp3"/>-->
            <div style="color:#fffff;margin-top: 00px;overflow-y: auto;height:400px" class="scrollbar">
            Table <%=activeid%> Details
            <table  width="900" style="text-align: center;border:1px solid blue;border-collapse: collapse;">


                <th style="border:1px solid blue;">Item name </th>

                   <th style="border:1px solid blue;">Quantity</th>
                   <th style="border:1px solid blue;">Status </th>
                   <th style="border:1px solid blue;">Action </th>

<%
Orders or=new Orders();
list=or.getData(activeid);
itr=list.iterator();
while(itr.hasNext()){
ActionForm af=(ActionForm) itr.next(); 
String name=af.getName();
String qt=af.getQuantity();
String st=af.getStatus();
String act=af.getKitchenAction();
%>
<tr>
                    <td style="border:1px solid blue;width:50%"align="left" ><%=name%> </td>

                   <td style="border:1px solid blue;"><%=qt%></td>
                   <td style="border:1px solid blue;"><%=st%> </td>
                   <td style="border:1px solid blue;"><%=act%> </td>
                  </tr>
                  <%
}
%>


            </table>

</div>
        </fieldset>
 <a href="#x" class="overlay" id="join_form"></a>
        <div class="popup" style="width:200px;height: 300px;">
            <h4>Checked out Tables</h4>
            <%
                       ArrayList lst=o.getCheckedOut();
                       Iterator it1=lst.iterator();
                       while(it1.hasNext()){
                       out.println(it1.next()+" is checked out");
                       }
            %>
            <a class="close" href="#close"></a>
        </div>
        </td>
    </tr>
</table>
    </body>
</html>

Answer 2

是的，知道了。tomcat 关闭端口的问题，我更改了它，现在它工作正常。