spring 中 filter listener servlet 配置

创建 三个类

分别实现 Filter  ServletContextListener  HttpServlet

在springboot 启动类中@bean加入

2 ，实现 ServletContextIntializer接口

@SpringBootApplication
public class DemoApplication implements ServletContextInitializer{

    public static void main(String[] args) {
        SpringApplication.run(DemoApplication.class, args);
    }

    @Override
    public void onStartup(ServletContext servletContext) throws ServletException {
        servletContext.addServlet("customServlet", new CustomServlet()).addMapping("/root");
        servletContext.addFilter("customfilter", new CustomFilter())
                        .addMappingForServletNames(EnumSet.of(DispatcherType.REQUEST), true, "customServlet");
        servletContext.addListener(new CustomListener());
    }
}

3. 注解方式  主类加上@ServletComponentScan     给三个分别加上注解

@WebServlet(urlPatterns="/index", name="customServlet")
public class CustomServlet extends HttpServlet{
   ....
}

@WebListener
public class CustomListener implements ServletContextListener{
   ....
}

@WebFilter(urlPatterns="/*")
public class CustomFilter implements Filter{
  ...
}

4.   自定义注解 实现  主类上加上此注解

@Target(value = {ElementType.TYPE})
@Retention(RetentionPolicy.RUNTIME)
@Documented
@Import(value = {FirstFilterConfiguration.class})
public @interface EnableFirstFilter {

}

注册配置的bean（

FirstFilterConfiguration.class

）

public class FirstFilterConfiguration {

    public static final Integer ORDER = Integer.MIN_VALUE;    

    @Bean
    public FilterRegistrationBean firstFilter(){
        FilterRegistrationBean registration = new FilterRegistrationBean();
        registration.setFilter(new FirstFilter());
        registration.addUrlPatterns("/*");
        registration.setName("firstFilter");
        registration.setOrder(ORDER);
        return registration;
    }
}

public class FirstFilter implements Filter {

    @Override
    public void destroy() {

    }

    @Override
    public void doFilter(ServletRequest srst, ServletResponse srsp, FilterChain chain)
            throws IOException, ServletException {
        chain.doFilter(srst, srsp);
    }

    @Override
    public void init(FilterConfig arg0) throws ServletException {

    }

}

原文地址：https://www.cnblogs.com/mxz1994/p/8215393.html