Tomcat启动中用于过滤器的ClassCastException

Question

Im getting an error like this. This is happend when i run the program and it did not run.it showed following error.

Jul 10, 2013 1:21:24 PM org.apache.catalina.core.AprLifecycleListener init
INFO: The APR based Apache Tomcat Native library which allows optimal performance in production environments was not found on the java.library.path: C:\Program Files\Java\jre6\bin;.;C:\Windows\Sun\Java\bin;C:\Windows\system32;C:\Windows;C:/Program Files/Java/jre6/bin/client;C:/Program Files/Java/jre6/bin;C:/Program Files/Java/jre6/lib/i386;C:\Windows\system32;C:\Windows;C:\Windows\System32\Wbem;C:\Windows\System32\WindowsPowerShell\v1.0\;C:\Program Files\Kaspersky Lab\Kaspersky Anti-Virus 6.0 for Windows Workstations MP4\;C:\Program Files\Java\jdk1.6.0_07/bin;C:\Program Files\MySQL\MySQL Server 5.2\bin;D:\common libs\com.mysql.jdbc_5.1.5.jar;;C:\Users\lcladmin\Documents\Softwares\java related\eclipse-jee-indigo-win32_2\eclipse;
Jul 10, 2013 1:21:24 PM org.apache.tomcat.util.digester.SetPropertiesRule begin
WARNING: [SetPropertiesRule]{Server/Service/Engine/Host/Context} Setting property 'source' to 'org.eclipse.jst.jee.server:BankDemoWeb' did not find a matching property.
Jul 10, 2013 1:21:24 PM org.apache.coyote.AbstractProtocol init
INFO: Initializing ProtocolHandler ["http-bio-8080"]
Jul 10, 2013 1:21:24 PM org.apache.coyote.AbstractProtocol init
INFO: Initializing ProtocolHandler ["ajp-bio-8009"]
Jul 10, 2013 1:21:24 PM org.apache.catalina.startup.Catalina load
INFO: Initialization processed in 552 ms
Jul 10, 2013 1:21:24 PM org.apache.catalina.core.StandardService startInternal
INFO: Starting service Catalina
Jul 10, 2013 1:21:24 PM org.apache.catalina.core.StandardEngine startInternal
INFO: Starting Servlet Engine: Apache Tomcat/7.0.41
Jul 10, 2013 1:21:25 PM org.apache.catalina.core.StandardContext filterStart
SEVERE: Exception starting filter FilterRequest
java.lang.ClassCastException: com.mobitel.bankdemo.web.FilterRequest cannot be cast to javax.servlet.Filter
    at org.apache.catalina.core.ApplicationFilterConfig.getFilter(ApplicationFilterConfig.java:260)
    at org.apache.catalina.core.ApplicationFilterConfig.<init>(ApplicationFilterConfig.java:107)
    at org.apache.catalina.core.StandardContext.filterStart(StandardContext.java:4746)
    at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5399)
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
    at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1559)
    at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1549)
    at java.util.concurrent.FutureTask$Sync.innerRun(Unknown Source)
    at java.util.concurrent.FutureTask.run(Unknown Source)
    at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(Unknown Source)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
    at java.lang.Thread.run(Unknown Source)
Jul 10, 2013 1:21:25 PM org.apache.catalina.core.StandardContext startInternal
SEVERE: Error filterStart
Jul 10, 2013 1:21:25 PM org.apache.catalina.core.StandardContext startInternal
SEVERE: Context [/BankDemoWeb] startup failed due to previous errors
Jul 10, 2013 1:21:25 PM org.apache.coyote.AbstractProtocol start
INFO: Starting ProtocolHandler ["http-bio-8080"]
Jul 10, 2013 1:21:25 PM org.apache.coyote.AbstractProtocol start
INFO: Starting ProtocolHandler ["ajp-bio-8009"]
Jul 10, 2013 1:21:25 PM org.apache.catalina.startup.Catalina start
INFO: Server startup in 533 ms

Can any one tell me the reason of getting this error? (Im doing a web java application using jsp,servlet,tomcat.)

Here my FilterRequest.java file code

package com.mobitel.bankdemo.web;

import java.io.IOException;
import java.util.ArrayList;
import java.util.StringTokenizer;
import java.util.logging.Filter;
import java.util.logging.LogRecord;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.RequestDispatcher;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;

import com.mobitel.bankdemo.domain.User;

public class FilterRequest implements Filter{
    private static final long serialVersionUID = 1L;
    FilterConfig filterConfig = null;
    public FilterRequest() {
        super();
    }
    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {       
    }
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    }
    public void init(FilterConfig filterConfig) throws ServletException {
        this.filterConfig = filterConfig;
    }
    public void doFilter(ServletRequest req, ServletResponse resp, FilterChain chain) throws ServletException, IOException {
            HttpServletRequest request = (HttpServletRequest) req;
            HttpServletResponse response = (HttpServletResponse) resp;
                      HttpSession session = request.getSession(true);
          User u = (User) session.getAttribute("loggedUser");
          System.out.println(u+"i");
          if (u!= null)
          {
             System.out.println(u+"u");
             chain.doFilter(req, resp);
             return;
          }else{
              String message = "Please Login!";             
              req.setAttribute("loginMsg", message);
              response.sendRedirect("login2.jsp");
          }             
    }
    public void destroy() {
        // do cleanup stuff
    }
    @Override
    public boolean isLoggable(LogRecord arg0) {
        // TODO Auto-generated method stub
        return false;
    }
}

web.xml

<?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_3_0.xsd" id="WebApp_ID" version="3.0">
  <display-name>BankDemoWeb</display-name>
  <welcome-file-list>
    <welcome-file>home.jsp</welcome-file>
  </welcome-file-list>

  <servlet>
    <servlet-name>AccountController</servlet-name>
    <servlet-class>com.mobitel.bankdemo.web.AccountControllerServlet</servlet-class>
  </servlet>
  <servlet-mapping>
    <servlet-name>AccountController</servlet-name>
    <url-pattern>/account</url-pattern>
  </servlet-mapping>

  <session-config>
    <session-timeout>5</session-timeout>
  </session-config>

   <filter>
        <filter-name>FilterRequest</filter-name>
        <filter-class>com.mobitel.bankdemo.web.FilterRequest</filter-class>             
  </filter>
  <filter-mapping>
        <filter-name>FilterRequest</filter-name>
        <url-pattern>/*</url-pattern>
  </filter-mapping> 

Answer 1

Here, you implements Filter:

public class FilterRequest implements Filter

but not the one you expected , see your import :

import java.util.logging.Filter;

you should replace it with:

import javax.servlet.Filter

Then, you should not redirect the user to the login page if he is already trying to access it (or it will result in an infinite loop with the filter) :

You should replace this if statement :

if (u!= null)

with:

if (u!= null || request.getServletPath().equals("/login2.jsp"))

Answer 2

java.lang.ClassCastException: com.mobitel.bankdemo.web.FilterRequest cannot be cast to javax.servlet.Filter

From the error it seems you have declared com.mobitel.bankdemo.web.FilterRequest as a Filter in your DD , but forgot to implement javax.servlet.Filter in your class.

You are implementing import java.util.logging.Filter; , you should implement javax.servlet.Filter .