网络应用程序。设置 servlet TrackingFilter 后不显示任何内容
Web app. doesn't display any content after I set servlet TrackingFilter
我使用 tomcat 创建了一个简单的网络应用程序来测试跟踪过滤器。问题是 webapp 在没有跟踪过滤器的情况下工作正常。但是,当我实施跟踪过滤器时,webapp 不显示任何内容。我能够在 eclipse 的控制台上看到跟踪信息,但在浏览器上什么也看不到。
我的跟踪过滤器代码:
package com.myapp.filters;
import java.io.IOException;
import java.net.InetAddress;
import java.util.Date;
import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletRequest;
public class TrackingFilter implements Filter{
private FilterConfig config =null;
@Override
public void destroy() {
// TODO Auto-generated method stub
}
@Override
public void doFilter(ServletRequest req, ServletResponse res, FilterChain chain) throws IOException, ServletException {
HttpServletRequest httpReq = (HttpServletRequest)req;
/*
* Date of website entering
*/
Date now = new Date();
String host = httpReq.getHeader("host");
String ip = InetAddress.getLocalHost().getHostAddress();
config.getServletContext().log("TrackingFilter. " + "Date: " + now + ", " + "host: " + host + ", " + "IP: " + ip);
System.out.println("Exiting tracking filtering");
}
@Override
public void init(FilterConfig config) throws ServletException {
this.config = config;
}
}
我的web.xml配置
<!-- Tracking Filter -->
<filter>
<filter-name>Tracking Filter</filter-name>
<filter-class>com.myapp.filters.TrackingFilter</filter-class>
</filter>
<filter-mapping>
<filter-name>Tracking Filter</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
那是因为过滤器打断了链条,不会将请求传播到下一个过滤器和 servlet。它应该包含
chain.doFilter(req, res);
我使用 tomcat 创建了一个简单的网络应用程序来测试跟踪过滤器。问题是 webapp 在没有跟踪过滤器的情况下工作正常。但是,当我实施跟踪过滤器时,webapp 不显示任何内容。我能够在 eclipse 的控制台上看到跟踪信息,但在浏览器上什么也看不到。
我的跟踪过滤器代码:
package com.myapp.filters;
import java.io.IOException;
import java.net.InetAddress;
import java.util.Date;
import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletRequest;
public class TrackingFilter implements Filter{
private FilterConfig config =null;
@Override
public void destroy() {
// TODO Auto-generated method stub
}
@Override
public void doFilter(ServletRequest req, ServletResponse res, FilterChain chain) throws IOException, ServletException {
HttpServletRequest httpReq = (HttpServletRequest)req;
/*
* Date of website entering
*/
Date now = new Date();
String host = httpReq.getHeader("host");
String ip = InetAddress.getLocalHost().getHostAddress();
config.getServletContext().log("TrackingFilter. " + "Date: " + now + ", " + "host: " + host + ", " + "IP: " + ip);
System.out.println("Exiting tracking filtering");
}
@Override
public void init(FilterConfig config) throws ServletException {
this.config = config;
}
}
我的web.xml配置
<!-- Tracking Filter -->
<filter>
<filter-name>Tracking Filter</filter-name>
<filter-class>com.myapp.filters.TrackingFilter</filter-class>
</filter>
<filter-mapping>
<filter-name>Tracking Filter</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
那是因为过滤器打断了链条,不会将请求传播到下一个过滤器和 servlet。它应该包含
chain.doFilter(req, res);