java HTTP 状态 500 - 内部服务器错误 - JSP - Glass Fish 服务器
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HTTP Status 500 - Internal Server Error - JSP - Glass Fish server
提问by Sathish Kothandam
As a beginner to Jsp and Java , I'm building a simple web application that displays data from data base to web page
作为 Jsp 和 Java 的初学者，我正在构建一个简单的 Web 应用程序，该应用程序将数据从数据库显示到网页
When i run the below code i'm getting the following error HTTP Status 500 - Internal Server Error
当我运行以下代码时，我收到以下错误HTTP 状态 500 - 内部服务器错误
Building web application in net beans and web server is Glass fish
在 net beans 和 web 服务器中构建 web 应用程序是玻璃鱼
Don't know what went wrong .Still searching Google but no luck yet
不知道出了什么问题。仍在搜索谷歌，但还没有运气
type Exception report
messageInternal Server Error
descriptionThe server encountered an internal error that prevented it from fulfilling this request.
exception
org.apache.jasper.JasperException: java.lang.NullPointerException
root cause
java.lang.NullPointerException
Update1:
更新1：
Warning: StandardWrapperValve[jsp]: Servlet.service() for servlet jsp threw exception
java.lang.NullPointerException
at org.apache.jsp.nextPage_jsp._jspService(nextPage_jsp.java:111)
at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:111)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:790)
at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:411)
at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:473)
at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:377)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:790)
at org.apache.catalina.core.StandardWrapper.service(StandardWrapper.java:1682)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:318)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:160)
at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:734)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:673)
at com.sun.enterprise.web.WebPipeline.invoke(WebPipeline.java:99)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:174)
at org.apache.catalina.connector.CoyoteAdapter.doService(CoyoteAdapter.java:415)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:282)
at com.sun.enterprise.v3.services.impl.ContainerMapper$HttpHandlerCallable.call(ContainerMapper.java:459)
at com.sun.enterprise.v3.services.impl.ContainerMapper.service(ContainerMapper.java:167)
at org.glassfish.grizzly.http.server.HttpHandler.runService(HttpHandler.java:201)
at org.glassfish.grizzly.http.server.HttpHandler.doHandle(HttpHandler.java:175)
at org.glassfish.grizzly.http.server.HttpServerFilter.handleRead(HttpServerFilter.java:235)
at org.glassfish.grizzly.filterchain.ExecutorResolver.execute(ExecutorResolver.java:119)
at org.glassfish.grizzly.filterchain.DefaultFilterChain.executeFilter(DefaultFilterChain.java:284)
at org.glassfish.grizzly.filterchain.DefaultFilterChain.executeChainPart(DefaultFilterChain.java:201)
at org.glassfish.grizzly.filterchain.DefaultFilterChain.execute(DefaultFilterChain.java:133)
at org.glassfish.grizzly.filterchain.DefaultFilterChain.process(DefaultFilterChain.java:112)
at org.glassfish.grizzly.ProcessorExecutor.execute(ProcessorExecutor.java:77)
at org.glassfish.grizzly.nio.transport.TCPNIOTransport.fireIOEvent(TCPNIOTransport.java:561)
at org.glassfish.grizzly.strategies.AbstractIOStrategy.fireIOEvent(AbstractIOStrategy.java:112)
at org.glassfish.grizzly.strategies.WorkerThreadIOStrategy.run0(WorkerThreadIOStrategy.java:117)
at org.glassfish.grizzly.strategies.WorkerThreadIOStrategy.access0(WorkerThreadIOStrategy.java:56)
at org.glassfish.grizzly.strategies.WorkerThreadIOStrategy$WorkerThreadRunnable.run(WorkerThreadIOStrategy.java:137)
at org.glassfish.grizzly.threadpool.AbstractThreadPool$Worker.doWork(AbstractThreadPool.java:565)
at org.glassfish.grizzly.threadpool.AbstractThreadPool$Worker.run(AbstractThreadPool.java:545)
at java.lang.Thread.run(Thread.java:745)
Index.jsp
索引.jsp
<%--
Document : index
Created on : Jan 1, 2015, 7:36:04 PM
Author : ksathis
--%>
<%@page contentType="text/html" pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Inside</title>
</head>
<body>
<h1>Inside</h1>
<form name="mainForm" action="nextPage.jsp" method="POST">
<table border="0">
<tbody>
<tr>
<td>DateRange</td>
<td><input type="radio" name="radioS" id="dateRadio" value="1" /></td>
<td><input type="date" name="date1" value="0" size="10" /></td>
<td><input type="date" name="date2" value="0" size="10" /></td>
</tr>
<tr>
<td>WeekNum</td>
<td><input type="radio" name="radioS" id="weekRadio" value="1" /></td>
<td><input type="text" name="weeknum1" id="weeknum1" value="0" size="10" /></td>
</tr>
<tr>
<td>MonthNum</td>
<td><input type="radio" name="radioS" id="monthRadio" value="1" /></td>
<td><input type="text" name="monthnum1" value="0" size="10" /></td>
</tr>
<tr>
<td></td>
<td></td>
<td><input type="reset" value="Clear" name="Clear" size="10"/><input type="submit" value="submit" name="Clear" size="10"/></td>
</tr>
</tbody>
</table>
</form>
</body>
</html>
Nextpage.jsp
下一页.jsp
<%--
Document : nextPage
Created on : Jan 1, 2015, 7:55:59 PM
Author : ksathis
--%>
<%@page import="java.sql.*" %>
<% Class.forName("com.mysql.jdbc.Driver"); %>
<%@page contentType="text/html" pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Result</title>
</head>
<body>
<h1>DIS SLA RESULT FOR THE WEEK !</h1>
<%!
public class imaging {
String URL = "jdbc:mysql://localhost:3306/database1";
String USERNAME = "root";
String PASSWORD = "password";
Connection connection = null;
PreparedStatement selectRetouch = null;
ResultSet resultSet = null;
public imaging() {
try {
connection = DriverManager.getConnection(URL, USERNAME, PASSWORD);
selectRetouch = connection.prepareStatement("select * from retouch limit 1 , ?");
} catch (SQLException e) {
e.printStackTrace();
}
}
public ResultSet imaging_Result(String limitone) {
try {
selectRetouch.setString(1, limitone);
resultSet = selectRetouch.executeQuery();
} catch (SQLException e) {
e.printStackTrace();
}
return resultSet;
}
}
%>
<%
String str = new String();
str = request.getParameter("weeknum1");
imaging image = new imaging();
ResultSet images = image.imaging_Result(str);
%>
<table border="1">
<tbody>
<tr>
<td>Retail_sku</td>
<td>Region</td>
</tr>
<% while (images.next()) {%>
<tr>
<td><%= images.getString("retail_sku")%></td>
<td><%= images.getString("region")%></td>
</tr>
<% }%>
</tbody>
</table>
</body>
</html>
采纳答案by ZakiMak
Please try first by rearranging your imports and declarations followed by driver loading later on as a scriptlet :
请首先尝试重新排列您的导入和声明，然后稍后将驱动程序加载为脚本：
<%@ page import="java.sql.*" %>
<%@ page contentType="text/html" pageEncoding="UTF-8"%>
<% Class.forName("com.mysql.jdbc.Driver"); %>
Next the class renaming is not okay. First letter of your class should be capital. So rename it to Imaging. It is better to define this class in your source package rather than declare inside JSP page and using it.
接下来类重命名是不行的。你班级的第一个字母应该是大写的。所以将其重命名为 Imaging。最好在源包中定义此类，而不是在 JSP 页面中声明并使用它。
The problem area is your PreparedStatement:
问题区域是您的 PreparedStatement：
selectRetouch.setString(1, limitone);
Since you are setting a limit value, the driver is expecting an Integer value and not a String. To get over this problem here is a workaround:
由于您正在设置一个限制值，驱动程序需要一个整数值而不是一个字符串。为了解决这个问题，这里有一个解决方法：
selectRetouch.setInt(1, Integer.parseInt(limitone));
To test this through URL you directly hit the link and pass the request parameter like this for example:
要通过 URL 进行测试，您可以直接点击链接并传递请求参数，例如：
http://localhost:8080/yourappname/yourpage.jsp?weeknum1=12
