* Examples that have been identified for this design are<br>
 * 1) Authentication Filters, 即用戶訪問權限過濾
 * 2) Logging and Auditing Filters, 日志過濾，可以記錄特殊用戶的特殊請求的記錄等
 * 3) Image conversion Filters
 * 4) Data compression Filters <br>
 * 5) Encryption Filters <br>
 * 6) Tokenizing Filters <br>
 * 7) Filters that trigger resource access events <br>
 * 8) XSL/T filters <br>
 * 9) Mime-type chain Filter <br>

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.stereotype.Component;

import javax.servlet.*;
import javax.servlet.http.HttpServletRequest;
import java.io.IOException;

// 必須添加注解，springmvc通過web.xml配置
@Component
public class TimeFilter implements Filter {
 private static final Logger LOG = LoggerFactory.getLogger(TimeFilter.class);

 @Override
 public void init(FilterConfig filterConfig) throws ServletException {
  LOG.info("初始化過濾器：{}", filterConfig.getFilterName());
 }

 @Override
 public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {
  LOG.info("start to doFilter");
  long startTime = System.currentTimeMillis();
  chain.doFilter(request, response);
  long endTime = System.currentTimeMillis();
  LOG.info("the request of {} consumes {}ms.", getUrlFrom(request), (endTime - startTime));
  LOG.info("end to doFilter");
 }

 @Override
 public void destroy() {
  LOG.info("銷毀過濾器");
 }

 private String getUrlFrom(ServletRequest servletRequest){
  if (servletRequest instanceof HttpServletRequest){
   return ((HttpServletRequest) servletRequest).getRequestURL().toString();
  }

  return "";
 }
}

@Configuration
public class WebConfig {
 /**
  * 注冊第三方過濾器
  * 功能與spring mvc中通過配置web.xml相同
  * @return
  */
 @Bean
 public FilterRegistrationBean thirdFilter(){
  ThirdPartFilter thirdPartFilter = new ThirdPartFilter();
  FilterRegistrationBean filterRegistrationBean = new FilterRegistrationBean() ;

  filterRegistrationBean.setFilter(thirdPartFilter);
  List<String > urls = new ArrayList<>();
  // 匹配所有請求路徑
  urls.add("/*");
  filterRegistrationBean.setUrlPatterns(urls);

  return filterRegistrationBean;
 }
}

@Component
public class TimeInterceptor implements HandlerInterceptor {
 private static final Logger LOG = LoggerFactory.getLogger(TimeInterceptor.class);
 @Override
 public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
  LOG.info("在請求處理之前進行調用（Controller方法調用之前）");
  request.setAttribute("startTime", System.currentTimeMillis());
  HandlerMethod handlerMethod = (HandlerMethod) handler;
  LOG.info("controller object is {}", handlerMethod.getBean().getClass().getName());
  LOG.info("controller method is {}", handlerMethod.getMethod());

  // 需要返回true，否則請求不會被控制器處理
  return true;
 }

 @Override
 public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {
  LOG.info("請求處理之后進行調用，但是在視圖被渲染之前（Controller方法調用之后），如果異常發(fā)生，則該方法不會被調用");
 }

 @Override
 public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {
  LOG.info("在整個請求結束之后被調用，也就是在DispatcherServlet 渲染了對應的視圖之后執(zhí)行（主要是用于進行資源清理工作）");
  long startTime = (long) request.getAttribute("startTime");
  LOG.info("time consume is {}", System.currentTimeMillis() - startTime);
 }

// java配置類
@Configuration
public class WebConfig implements WebMvcConfigurer {
 @Autowired
 private TimeInterceptor timeInterceptor;

 @Override
 public void addInterceptors(InterceptorRegistry registry){
  registry.addInterceptor(timeInterceptor);
 }
}

@Aspect
@Component
public class TimeAspect {
 private static final Logger LOG = LoggerFactory.getLogger(TimeAspect.class);

 @Around("execution(* me.ifight.controller.*.*(..))")
 public Object handleControllerMethod(ProceedingJoinPoint proceedingJoinPoint) throws Throwable{
  LOG.info("切片開始。。。");
  long startTime = System.currentTimeMillis();

  // 獲取請求入參
  Object[] args = proceedingJoinPoint.getArgs();
  Arrays.stream(args).forEach(arg -> LOG.info("arg is {}", arg));

  // 獲取相應
  Object response = proceedingJoinPoint.proceed();

  long endTime = System.currentTimeMillis();
  LOG.info("請求:{}, 耗時{}ms", proceedingJoinPoint.getSignature(), (endTime - startTime));
  LOG.info("切片結束。。。");
  return null;
 }
}