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編輯：我能夠通過將index.jsp重命名爲hi.jsp來解決此問題。任何人都知道我爲什麼會遇到文件名問題？NullPointerException嘗試獲取index.jsp設置
問題： 我寫了使用Java /春web應用程序的後端組件，並通過Spring註解迷上它到Tomcat：
@Controller
public class WorkerSubmitterController {
@RequestMapping(value = {"/start"}, method = RequestMethod.GET, produces = "text/plain")
@ResponseBody
public ResponseEntity<String> start() throws Exception {
return new ResponseEntity<String>("Started", HttpStatus.OK);
}
}
我配置Servlet是這樣的：
public class WebInitializer implements WebApplicationInitializer {
@Override
public void onStartup(ServletContext container) {
// Create the dispatcher servlet's Spring application context
AnnotationConfigWebApplicationContext dispatcherContext = new AnnotationConfigWebApplicationContext();
dispatcherContext.scan("com.myProject.someName");
// Manage the lifecycle of the root application context
container.addListener(new ContextLoaderListener(dispatcherContext));
// Register and map the dispatcher servlet
ServletRegistration.Dynamic dispatcher =
container.addServlet("dispatcher", new DispatcherServlet(dispatcherContext));
dispatcher.setLoadOnStartup(1);
Set<String> mappingConflicts = dispatcher.addMapping("/");
}
}
這工作正常當我去localhost:8080/start
但是，現在我試試通過獲得index.jsp工作來編寫前端。我創建了一個index.jsp文件/webapp/WEB-INF/下有以下情況：
<html>
<head>
<title>Hello world</title>
</head>
<body>
我加了web.xml文件：
<web-app id="WebApp_ID" version="2.4"
xmlns="http://java.sun.com/xml/ns/j2ee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee
http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd">
<servlet>
<servlet-name>home</servlet-name>
<jsp-file>/index.jsp</jsp-file>
</servlet>
<servlet-mapping>
<servlet-name>home</servlet-name>
<url-pattern>/home</url-pattern>
</servlet-mapping>
</web-app>
當我訪問localhost:8080/home 我得到這個錯誤：
HTTP ERROR 404
Problem accessing /home. Reason:
Not Found
Powered by Jetty://
和服務器端顯示：
2013-10-08 20:27:31.652:WARN:oejs.ServletHandler:/home
java.lang.NullPointerException
at java.net.URLEncoder.encode(URLEncoder.java:205)
at java.net.URLEncoder.encode(URLEncoder.java:171)
at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:474)
at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:378)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:848)
at org.eclipse.jetty.servlet.ServletHolder.handle(ServletHolder.java:669)
at org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:457)
at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:137)
at org.eclipse.jetty.security.SecurityHandler.handle(SecurityHandler.java:557)
at org.eclipse.jetty.server.session.SessionHandler.doHandle(SessionHandler.java:231)
at org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:1075)
at org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:384)
at org.eclipse.jetty.server.session.SessionHandler.doScope(SessionHandler.java:193)
at org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:1009)
at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:135)
at org.eclipse.jetty.server.handler.ContextHandlerCollection.handle(ContextHandlerCollection.java:255)
at org.eclipse.jetty.server.handler.HandlerCollection.handle(HandlerCollection.java:154)
at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:116)
at org.eclipse.jetty.server.Server.handle(Server.java:368)
at org.eclipse.jetty.server.AbstractHttpConnection.handleRequest(AbstractHttpConnection.java:489)
at org.eclipse.jetty.server.AbstractHttpConnection.headerComplete(AbstractHttpConnection.java:942)
at org.eclipse.jetty.server.AbstractHttpConnection$RequestHandler.headerComplete(AbstractHttpConnection.java:1004)
at org.eclipse.jetty.http.HttpParser.parseNext(HttpParser.java:640)
at org.eclipse.jetty.http.HttpParser.parseAvailable(HttpParser.java:235)
at org.eclipse.jetty.server.AsyncHttpConnection.handle(AsyncHttpConnection.java:82)
at org.eclipse.jetty.io.nio.SelectChannelEndPoint.handle(SelectChannelEndPoint.java:628)
at org.eclipse.jetty.io.nio.SelectChannelEndPoint$1.run(SelectChannelEndPoint.java:52)
at org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:608)
at org.eclipse.jetty.util.thread.QueuedThreadPool$3.run(QueuedThreadPool.java:543)
at java.lang.Thread.run(Thread.java:724)
我在做什麼錯？我錯過了讓jsp頁面工作的步驟嗎？ index.jsp不正確？我試過修改index.jsp只是hello，彈出同樣的錯誤。另外，我已經試過移動index.jsp文件，找到問題的根源，並且錯誤消失，但後來我得到
Oct 08, 2013 9:58:38 PM org.apache.jasper.servlet.JspServlet serviceJspFile
SEVERE: PWC6117: File "%2FUsers%2FuserName%2Fpersonal%2Friver%2Fsrc%2Fmain%2Fwebapp%2FWEB-INF%2Findex.jsp" not found
所以我想這個問題是關係到我的JSP文件。
它似乎是一個警告，而不是一個錯誤。你沒有聲明文件的編碼？ – Floris
我曾經在index.jsp的頂部有<％@ page contentType =「text/html; charset = UTF-8」language =「java」％>，但它仍然給我提供了相同的錯誤 – Popcorn
我也是嘗試添加 – Popcorn