1. 程式人生 > >spring中過濾器(filter)、攔截器(interceptor)和切面(aop)的執行順序

spring中過濾器(filter)、攔截器(interceptor)和切面(aop)的執行順序

1.程式執行的順序是先進過濾器,再進攔截器,最後進切面。注意:如果攔截器中preHandle方法返回的為false時,則無法進入切面,例子如下

@RestController
@RequestMapping("/user")
public class UserController {

    @GetMapping("/{id:\\d+}")
	@JsonView(User.UserDetailView.class)
	public User getInfo(@PathVariable String id) {
		User user = new User();
		user.setUsername("tom");
		return user;
	}
}

編寫方法的過濾器:

@Component
public class TimeFilter implements Filter {

	/* (non-Javadoc)
	 * @see javax.servlet.Filter#init(javax.servlet.FilterConfig)
	 */
	@Override
	public void init(FilterConfig filterConfig) throws ServletException {
		System.out.println("time filter init");

	}

	/* (non-Javadoc)
	 * @see javax.servlet.Filter#doFilter(javax.servlet.ServletRequest, javax.servlet.ServletResponse, javax.servlet.FilterChain)
	 */
	@Override
	public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)
			throws IOException, ServletException {
		System.out.println("time filter start");
		long start = new Date().getTime();
		chain.doFilter(request, response);
		System.out.println("time filter:"+ (new Date().getTime() - start));
		System.out.println("time filter finish");

	}

	/* (non-Javadoc)
	 * @see javax.servlet.Filter#destroy()
	 */
	@Override
	public void destroy() {
		System.out.println("time filter destroy");

	}

}

編寫方法的攔截器:

@Component
public class TimeInterceptor implements HandlerInterceptor {

	
	@Override
	public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler)
			throws Exception {
		System.out.println("preHandle");
		System.out.println(((HandlerMethod)handler).getBean().getClass().getName());
		System.out.println(((HandlerMethod)handler).getMethod().getName());
		request.setAttribute("startTime", new Date().getTime());
		return true;
	}

	
	@Override
	public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler,
			ModelAndView modelAndView) throws Exception {
		System.out.println("postHandle");
		Long start = (Long)request.getAttribute("startTime");
		System.out.println("time interceptor 耗時:"+ (new Date().getTime() - start));
	}

	
	@Override
	public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex)
			throws Exception {
		System.out.println("afterCompletion");
		Long start = (Long) request.getAttribute("startTime");
		System.out.println("time interceptor 耗時:"+ (new Date().getTime() - start));
		System.out.println("ex is "+ex);
	}

}

編寫方法的切面:

@Aspect
@Component
public class TimeAspect {

	@Before("execution(public * com.hu.web.controller.UserController.*(..))")
	public Object handlerControllerMethod() throws Throwable {
		System.out.println("time aspect start");			
		return new Object();
	}
}

執行結果:1、當攔截器中preHandle的方法返回為true時:

time filter start
preHandle
com.hu.web.controller.UserController$$EnhancerBySpringCGLIB$$b0bb0dcf
getInfo
time aspect start
postHandle
time interceptor 耗時:76
afterCompletion
time interceptor 耗時:76
ex is null
time filter:92
time filter finish
time filter start
time filter:46
time filter finish

2、當攔截器中preHandle的方法返回為false時:

time filter start
preHandle
com.hu.web.controller.UserController$$EnhancerBySpringCGLIB$$b0bb0dcf
getInfo
time filter:12
time filter finish
time filter start
time filter:23
time filter finish

2.當程式有異常丟擲時,回先進入切面,然後在進入自定義的ControllerAdvice中。