过滤器和拦截器

拦截器

tip

如果遇到路由404，那么会默认访问对应路由下的静态资源，这导致在访问404接口时拦截器会跑两次。（问题不大，但是强迫症表示不能接受。）

可以通过配置静态资源路径的方式去解决。

application.yml

spring:
  mvc:
    static-path-pattern: /static/**

写拦截器

package com.kinda.springBootDemo.interceptor;

import lombok.extern.slf4j.Slf4j;
import org.springframework.stereotype.Component;
import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

@Component
@Slf4j
public class Oauth2Interceptor implements HandlerInterceptor {
    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
        log.info("鉴权标识符: {}", request.getHeader("authorization"));
        return true;
    }

    @Override
    public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {
        HandlerInterceptor.super.postHandle(request, response, handler, modelAndView);
    }

    @Override
    public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {
        HandlerInterceptor.super.afterCompletion(request, response, handler, ex);
    }
}

注册自定义拦截器

package com.kinda.springBootDemo.interceptor;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.servlet.config.annotation.InterceptorRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;

/**
 * 配置拦截器
 * 此处绑定接口鉴权部分
 */
@Configuration
public class interceptor implements WebMvcConfigurer {
    @Autowired
    private Oauth2Interceptor oauth2Interceptor;
    @Override
    public void addInterceptors(InterceptorRegistry registry) {
        registry.addInterceptor(oauth2Interceptor);
    }
}

过滤器

使用spring boot提供的FilterRegistrationBean注册Filter。

先定义Filter

 
package com.corwien.filter;
import javax.servlet.*;
import java.io.IOException;
public class MyFilter implements Filter {
    @Override public void init(FilterConfig filterConfig) throws ServletException {
 
    }
    @Override public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException { // do something 处理request 或response
     // doFilter()方法中的servletRequest参数的类型是ServletRequest，需要转换为HttpServletRequest类型方便调用某些方法
      System.out.println("filter1"); // 调用filter链中的下一个filter
 
    HttpServletRequest request = (HttpServletRequest) servletRequest;
        HttpServletResponse response = (HttpServletResponse) servletResponse;
 
        String ip = request.getRemoteAddr();
        String url = request.getRequestURL().toString();
        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        Date d = new Date();
        String date = sdf.format(d);
 
        System.out.printf("%s %s 访问了 %s%n", date, ip, url);
        
        filterChain.doFilter(request, response);
    }
    @Override public void destroy() {
 
    }
}

注册自定义Filter

@Configuration
public class FilterConfig {
 
    @Bean
    public FilterRegistrationBean registrationBean() {
        FilterRegistrationBean filterRegistrationBean = new FilterRegistrationBean(new MyFilter());
        filterRegistrationBean.addUrlPatterns("/*");
        return filterRegistrationBean;
    }
}