springboot配置过滤器

Spring Boot中使用过滤器可以通过实现Filter接口来实现，也可以通过注解@WebFilter来实现。下面分别介绍这两种方式的实现方式。

1. 实现Filter接口

首先创建一个过滤器类，实现Filter接口：

public class MyFilter implements Filter {
 
    @Override
    public void init(FilterConfig filterConfig) throws ServletException {
        System.out.println("过滤器初始化");
    }
 
    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        System.out.println("执行过滤操作");
        filterChain.doFilter(servletRequest, servletResponse);
    }
 
    @Override
    public void destroy() {
        System.out.println("过滤器销毁");
    }
}

然后在Spring Boot的配置类中将该过滤器加入到过滤器链中：

@Configuration
public class WebConfig {
 
    @Bean
    public FilterRegistrationBean<MyFilter> filterRegistrationBean() {
        FilterRegistrationBean<MyFilter> registrationBean = new FilterRegistrationBean<>();
        registrationBean.setFilter(new MyFilter());
        registrationBean.addUrlPatterns("/*");
        registrationBean.setName("MyFilter");
        registrationBean.setOrder(1);
        return registrationBean;
    }
}

2. 使用@WebFilter注解

直接在过滤器类上加上@WebFilter注解即可：

@WebFilter(filterName = "MyFilter", urlPatterns = "/*")
public class MyFilter implements Filter {
 
    @Override
    public void init(FilterConfig filterConfig) throws ServletException {
        System.out.println("过滤器初始化");
    }
 
    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        System.out.println("执行过滤操作");
        filterChain.doFilter(servletRequest, servletResponse);
    }
 
    @Override
    public void destroy() {
        System.out.println("过滤器销毁");
    }
}