Servlet web.xml过滤器-未找到类异常 [英] Servlet web.xml filter -- Class not found exception

问题描述

我在设置过滤器时遇到问题- 我在web.xml中定义的过滤器看起来像这样

I am having a problem setting up the filter - the filter I have defined in web.xml looks like this

  <filter>
   <filter-name>Log</filter-name>
   <filter-class>test.log</filter-class> 
 </filter>
 <filter-mapping>
   <filter-name>Log</filter-name>
   <url-pattern>/*</url-pattern>
 </filter-mapping>

但是我收到以下错误-

SEVERE: Exception starting filter Log
java.lang.ClassNotFoundException: test.log
at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1711)
at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1556)
at org.apache.catalina.core.DefaultInstanceManager.loadClass(DefaultInstanceManager.java:532)
at org.apache.catalina.core.DefaultInstanceManager.loadClassMaybePrivileged(DefaultInstanceManager.java:514)
at org.apache.catalina.core.DefaultInstanceManager.newInstance(DefaultInstanceManager.java:133)
at org.apache.catalina.core.ApplicationFilterConfig.getFilter(ApplicationFilterConfig.java:256)
at org.apache.catalina.core.ApplicationFilterConfig.setFilterDef(ApplicationFilterConfig.java:382)
at org.apache.catalina.core.ApplicationFilterConfig.<init>(ApplicationFilterConfig.java:103)
at org.apache.catalina.core.StandardContext.filterStart(StandardContext.java:4650)
at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5306)
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$Sync.innerRun(FutureTask.java:334)
at java.util.concurrent.FutureTask.run(FutureTask.java:166)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1110)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:603)
at java.lang.Thread.run(Thread.java:722)

我已经定义了类，但是由于某种原因，我得到了Classnotfoundexcetion.有人可以帮我吗?

I have the class defined but for some reason I am getting the Classnotfoundexcetion. Can someone help me out?

编辑---

我有一个名为test的软件包和一个名为log的类.

I have a package called test and a class called log.

             package test;
    import java.io.*;
    import javax.servlet.*;
    import javax.servlet.http.*;
    import java.util.*;

    // Implements Filter class
     public class log implements Filter  {
         public void  init(FilterConfig config) {

          }
         public void  doFilter(ServletRequest request, 
             ServletResponse response,
             FilterChain chain) 
             throws java.io.IOException, ServletException {

  // Get the IP address of client machine.   
  String ipAddress = request.getRemoteAddr();

  // Log the IP address and current timestamp.
  System.out.println("IP "+ ipAddress + ", Time "
                                   + new Date().toString());

  // Pass request back down the filter chain
  chain.doFilter(request,response);
  }
   public void destroy( ){
      /* Called before the Filter instance is removed 
      from service by the web container*/
  }
 }

谢谢

推荐答案

filter-class参数必须是应实现Filter接口的Java类.你能检查一下是否是这种情况吗?

The filter-class parameter needs to be a Java class that should implement the Filter interface. Can you check if that's the case with you?

检查此示例以获取指导:

Check this example for guidance:

http://viralpatel.net /blogs/tutorial-java-servlet-filter-example-using-eclipse-apache-tomcat/

从上面的链接:

<filter>
    <filter-name>LogFilter</filter-name>
    <filter-class>
        net.viralpatel.servlet.filters.LogFilter
    </filter-class>
    <init-param>
        <param-name>test-param</param-name>
        <param-value>This parameter is for testing.</param-value>
    </init-param>
</filter>
<filter-mapping>
    <filter-name>LogFilter</filter-name>
    <url-pattern>/*</url-pattern>
</filter-mapping>



public class LogFilter implements Filter {

    public void doFilter(ServletRequest req, ServletResponse res,
            FilterChain chain) throws IOException, ServletException {...
    }
 }

这篇关于Servlet web.xml过滤器-未找到类异常的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！