GRAVE: "Servlet.service()" pour la servlet BookList a généré une exception
BONJOUR,
j'ai une petite erreur, pouvez vous m'aider
merci
voila le code de l'erreur
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| GRAVE: "Servlet.service()" pour la servlet BookList a généré une exception
java.lang.NullPointerException
at javax.servlet.GenericServlet.getServletContext(GenericServlet.java:160)
at de.laliluna.tutorial.library.servlets.BookList.doGet(BookList.java:63)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:617)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:298)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:859)
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:588)
at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:489)
at java.lang.Thread.run(Unknown Source) |
la servlet concernée
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| public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
//hole die session des requests
HttpSession session = request.getSession();
//initialisiere die Datenbank Klasse
SimulateDB simulateDB = new SimulateDB();
//lies alle B�cher aus der Datenbank Klasse
Collection collection = simulateDB.getAllBooks(session);
//setze die zur�ck gegebene Liste der B�cher im Request
request.setAttribute("books", collection);
//hole den Request Dispatcher f�r die JSP Datei
RequestDispatcher dispatcher = getServletContext().getRequestDispatcher("/bookList.jsp");
//leite auf die JSP Datei zum Anzeigen der Liste weiter
dispatcher.forward(request, response);
} |
la ligne 63 est : RequestDispatcher dispatcher = getServletContext().getRequestDispatcher("/bookList.jsp");
et mon web.xml est
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| <?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" id="WebApp_ID" version="2.5">
<display-name>LibraryWeb</display-name>
<welcome-file-list>
<welcome-file>index.html</welcome-file>
<welcome-file>index.htm</welcome-file>
<welcome-file>index.jsp</welcome-file>
<welcome-file>default.html</welcome-file>
<welcome-file>default.htm</welcome-file>
<welcome-file>default.jsp</welcome-file>
</welcome-file-list>
<servlet>
<servlet-name>BookList</servlet-name>
<servlet-class>de.laliluna.tutorial.library.servlets.BookList</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>BookList</servlet-name>
<url-pattern>/bookList</url-pattern>
</servlet-mapping>
<servlet>
<servlet-name>BookEdit</servlet-name>
<servlet-class>de.laliluna.tutorial.library.servlets.BookEdit</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>BookEdit</servlet-name>
<url-pattern>/bookEdit</url-pattern>
</servlet-mapping>
</web-app> |
