springboot过滤器

要新建Filter的继承类和WebConfiguration将自定义 Filter 加入过滤链

会导致requestBody为null，暂时不适用

方式一

1 自定义过滤器

MyFilter

import javax.servlet.*;
import javax.servlet.http.HttpServletRequest;
import java.io.IOException;
/**
 * @Description
 * @Author 田云
 * @Date 2019/3/7 10:04
 * @Version 1.0
 */
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 {
        HttpServletRequest request = (HttpServletRequest) servletRequest;
        System.out.println("拦截的请求："+request.getRequestURI());
        filterChain.doFilter(servletRequest, servletResponse);
    }
    @Override
    public void destroy() {
    }
}

2、加入过滤器链

filter/WebConfiguration.java

import org.springframework.boot.web.servlet.FilterRegistrationBean;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
/**
 * @Description
 * @Author 田云
 * @Date 2019/3/7 10:23
 * @Version 1.0
 */
@Configuration
public class WebConfiguration {
    @Bean
    public FilterRegistrationBean testFilterRegistration() {
        FilterRegistrationBean registration = new FilterRegistrationBean();
        registration.setFilter(new MyFilter());
        registration.addUrlPatterns("/*");
        registration.setName("MyFilter");
        registration.setOrder(6);
        return registration;
    }
    // 另一个自定义的过滤，Order表示顺序，小的先执行
    @Bean
    public FilterRegistrationBean test2FilterRegistration() {
        FilterRegistrationBean registration = new FilterRegistrationBean();
        registration.setFilter(new MyFilter2());
        registration.addUrlPatterns("/*");
        registration.setName("MyFilter2");
        registration.setOrder(1);
        return registration;
    }
}

方式二（推荐）

1、添加webfilter注解

import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import java.io.IOException;
/**
 * created with IntelliJ IDEA.
 * author: fxbin
 * date: 2018/9/9
 * time: 14:22
 * description:
 */
@WebFilter(filterName = "myFilter", urlPatterns = "/*")
public class MyFilter implements Filter {
    @Override
    public void init(FilterConfig filterConfig) throws ServletException {
        System.out.println("init...");
    }
    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        HttpServletRequest request = (HttpServletRequest) servletRequest;
        String requestURI = request.getRequestURI();
        if(requestURI.contains("my")){
            System.out.println("成功啦。。。, 请求URI是:" + requestURI);
        }
        filterChain.doFilter(request, servletResponse);
    }
    @Override
    public void destroy() {
        System.out.println("destroy...");
    }
}

2、启动类添加@ServletComponentScan注解

跨域处理

import lombok.extern.slf4j.Slf4j;
import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
@WebFilter
public class CorsFilter implements Filter {
    @Override
    public void doFilter(ServletRequest req, ServletResponse res, FilterChain chain) throws IOException, ServletException {
        HttpServletResponse response = (HttpServletResponse) res;
        response.setHeader("Access-Control-Allow-Origin", "*");
        response.setHeader("Access-Control-Allow-Methods", "POST, GET, OPTIONS, DELETE");
        response.setHeader("Access-Control-Max-Age", "3600");
        response.setHeader("Access-Control-Allow-Headers", "x-requested-with");
        chain.doFilter(req, res);
    }
    public void init(FilterConfig filterConfig) {
        // something init
    }
    public void destroy() {
        // destroy something
    }
}