filter 过滤器

1,实现  Filter 接口，重写init 方法

public class AdminLoginFilter implements Filter {
    static Log logger = LogFactory.getLog(AdminLoginFilter.class);
    @Override
    public void init(FilterConfig filterConfig) throws ServletException {
        logger.debug("logger过滤器的init执行");
    }
    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        logger.debug("logger过滤器doFilter开始执行");
        filterChain.doFilter(servletRequest, servletResponse);
        logger.debug("logger接口执行完毕");
    }
    @Override
    public void destroy() {
    }
}

2，Configuration 标记为配置类， bean方式注入 FilterRegistrationBean  到ioc容器

@Configuration
public class FilterConfig {
    @Bean
    public FilterRegistrationBean registFilter() {
        FilterRegistrationBean registration = new FilterRegistrationBean();
        registration.setFilter(new AdminLoginFilter());
        registration.addUrlPatterns("/*");          //url的匹配模式
        registration.setName("LogCostFilter");      //过滤器名称
        registration.setOrder(1);                   //执行顺序
        return registration;
    }
}