一、使用原生Servlet API(推荐)
@Slf4j@WebFilter(urlPatterns={"/css/*","/images/*"}) //mypublic class MyFilter implements Filter {@Overridepublic void init(FilterConfig filterConfig) throws ServletException {log.info("MyFilter初始化完成");}@Overridepublic void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {log.info("MyFilter工作");chain.doFilter(request,response);}@Overridepublic void destroy() {log.info("MyFilter销毁");}}-------------------------------------------------------------------------------@WebServlet(urlPatterns = "/my")public class MyServlet extends HttpServlet {@Overrideprotected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {resp.getWriter().write("66666");}}-------------------------------------------------------------------------------@Slf4j@WebListenerpublic class MySwervletContextListener implements ServletContextListener {@Overridepublic void contextInitialized(ServletContextEvent sce) {log.info("MySwervletContextListener监听到项目初始化完成");}@Overridepublic void contextDestroyed(ServletContextEvent sce) {log.info("MySwervletContextListener监听到项目销毁");}}
利用@ServletComponentScan扫描进来
@MapperScan("com.aa.admin.mapper")@ServletComponentScan(basePackages = "com.aa.admin")@SpringBootApplication(exclude = RedisAutoConfiguration.class)public class Boot05WebAdminApplication {public static void main(String[] args) {SpringApplication.run(Boot05WebAdminApplication.class, args);}}
二、使用RegistrationBean
ServletRegistrationBean, FilterRegistrationBean, and ServletListenerRegistrationBean
@Configurationpublic class MyRegistConfig {@Beanpublic ServletRegistrationBean myServlet(){MyServlet myServlet = new MyServlet();return new ServletRegistrationBean(myServlet,"/my","/my02");}@Beanpublic FilterRegistrationBean myFilter(){MyFilter myFilter = new MyFilter();// return new FilterRegistrationBean(myFilter,myServlet());FilterRegistrationBean filterRegistrationBean = new FilterRegistrationBean(myFilter);filterRegistrationBean.setUrlPatterns(Arrays.asList("/my","/css/*"));return filterRegistrationBean;}@Beanpublic ServletListenerRegistrationBean myListener(){MySwervletContextListener mySwervletContextListener = new MySwervletContextListener();return new ServletListenerRegistrationBean(mySwervletContextListener);}}
三、扩展：DispatchServlet 如何注册进来
容器中自动配置了 DispatcherServlet 属性绑定到 WebMvcProperties；对应的配置文件配置项是 spring.mvc。@Configuration(proxyBeanMethods = false)@Conditional({DispatcherServletAutoConfiguration.DispatcherServletRegistrationCondition.class})@ConditionalOnClass({ServletRegistration.class})@EnableConfigurationProperties({WebMvcProperties.class})@Import({DispatcherServletAutoConfiguration.DispatcherServletConfiguration.class})protected static class DispatcherServletRegistrationConfiguration {protected DispatcherServletRegistrationConfiguration() {}@Bean(name = {"dispatcherServletRegistration"})@ConditionalOnBean(value = {DispatcherServlet.class},name = {"dispatcherServlet"})public DispatcherServletRegistrationBean dispatcherServletRegistration(DispatcherServlet dispatcherServlet, WebMvcProperties webMvcProperties, ObjectProvider<MultipartConfigElement> multipartConfig) {DispatcherServletRegistrationBean registration = new DispatcherServletRegistrationBean(dispatcherServlet, webMvcProperties.getServlet().getPath());registration.setName("dispatcherServlet");registration.setLoadOnStartup(webMvcProperties.getServlet().getLoadOnStartup());multipartConfig.ifAvailable(registration::setMultipartConfig);return registration;}}
通过 ServletRegistrationBean 把 DispatcherServlet 配置进来。springboot默认映射的是 / 路径。
Tomcat-Servlet；
多个Servlet都能处理到同一层路径，精确优选原则
A： /my/
B： /my/1
如果访问 /my/1 那么由B处理，如果访问/my/2，那么由A处理
