spring boot過濾器和攔截器 demo

攔截器定義:

@WebServlet
public class ActionInterceptor implements HandlerInterceptor {

    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler)
            throws Exception {
        // System.out.println(">>>MyInterceptor1>>>>>>>在請求處理之前進行調用（Controller方法調用之前）");

        // 獲取系統時間
        Calendar ca = Calendar.getInstance();
        int hour = ca.get(Calendar.HOUR_OF_DAY);
        // 設置限制運行時間 0-4點
        if (hour < 4) {
            return true;
        }
        return false;
    }

    @Override
    public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler,
            ModelAndView modelAndView) throws Exception {
        // System.out.println(">>>MyInterceptor1>>>>>>>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）");

    }

    @Override
    public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex)
            throws Exception {
        // System.out.println(">>>MyInterceptor1>>>>>>>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行（主要是用於進行資源清理工作）");
    }
}

攔截器使用:  關於注解 我使用的是@Component  其實也可能聲明成配置

@Component
public class ApplicationConfig {extends WebMvcConfigurerAdapter 

    @Override
    public void addInterceptors(InterceptorRegistry registry) {
        // 多個攔截器組成一個攔截器鏈
        // addPathPatterns 用於添加攔截規則
        // excludePathPatterns 用戶排除攔截
        registry.addInterceptor(new ActionInterceptor()).addPathPatterns("/service/extract/json/**");
        super.addInterceptors(registry);
    }
}

 

 

過濾器:

定義:

public class ActionFilter implements Filter {

    @Override
    public void init(FilterConfig filterConfig) throws ServletException {

    }

    @Override
    public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)
            throws IOException, ServletException {
        // 獲取系統時間
        Calendar ca = Calendar.getInstance();
        int hour = ca.get(Calendar.HOUR_OF_DAY);
        // 設置限制運行時間 0-4點
        if (hour < 4) {
            HttpServletResponse httpResponse = (HttpServletResponse) response;
            httpResponse.setCharacterEncoding("UTF-8");
            httpResponse.setContentType("application/json; charset=utf-8");
            
            // 消息
            Map<String, Object> messageMap = new HashMap<>();
            messageMap.put("status", "1");
            messageMap.put("message", "此接口可以請求時間為:0-4點");
            ObjectMapper objectMapper=new ObjectMapper();
            String writeValueAsString = objectMapper.writeValueAsString(messageMap);
            response.getWriter().write(writeValueAsString);
            
        } else {
            chain.doFilter(request, response);
        }

    }

    @Override
    public void destroy() {

    }

}

使用:

@Component
public class ApplicationConfig { 


    @Bean
    public FilterRegistrationBean  filterRegistrationBean() {
        FilterRegistrationBean registrationBean = new FilterRegistrationBean();
        ActionFilter actionFilter = new ActionFilter();
        registrationBean.setFilter(actionFilter);
        List<String> urlPatterns = new ArrayList<String>();
        urlPatterns.add("/service/extract/json/*");
        registrationBean.setUrlPatterns(urlPatterns);
        return registrationBean;
    }
    

}