javaweb中添加过滤器页面出现404错误

[uniquewdl]

<filter>
<filter-name>CountFilter</filter-name>
<filter-class>com.filter.count.CountFilter</filter-class>
</filter>
<filter-mapping>
<filter-name>CountFilter</filter-name>
<url-pattern>/index.jsp</url-pattern>
</filter-mapping>


package com.filter.count;

import java.io.IOException;
import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.annotation.WebFilter;
import javax.servlet.annotation.WebInitParam;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

public class CountFilter implements Filter {
private int count;
@Override
public void destroy() {
// TODO Auto-generated method stub

}
@Override
public void doFilter(ServletRequest arg0, ServletResponse arg1,
FilterChain arg2) throws IOException, ServletException {
// TODO Auto-generated method stub
HttpServletRequest request=(HttpServletRequest)arg0;
HttpServletResponse response=(HttpServletResponse)arg1;
ServletContext context=request.getServletContext();
context.setAttribute("count", count);
arg2.doFilter(arg0,arg1);
}
@Override
public void init(FilterConfig arg0) throws ServletException {
// TODO Auto-generated method stub
String param=arg0.getInitParameter("count");
count =Integer.valueOf("param");
}
}

[qq_24065257]

看下你的web.xml文件，以及你的页面文件