请求翻译一下 chain.doFilter(request, response)这句代码的意思。

@WebFilter("/*")
public class IPFilter implements Filter {
public void init(FilterConfig config) throws ServletException {
System.out.println("IBEN");
}

@Override
public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws ServletException, IOException {
    request.setCharacterEncoding("utf-8");
    response.setContentType("text/html;charset=utf-8");
    String clientIp = request.getRemoteAddr();
    System.out.println(clientIp);
    if (!"192.168.3.6".equals(clientIp))
        return;
    chain.doFilter(request, response);
    System.out.println("出方向执行");
}

public void destroy() {
}

}

web 开发的拦截器，chain.doFilter会进入下一个拦截器进行逻辑判断，你图中的拦截器是进行ip判断，在进入真正的接口前一般会有多个拦截器组成一个拦截链，比如对用户名，密码判断，特殊字符处理请求资源判断等

执行后面的过滤链