springBoot注册3大组件

1 编写Filter Servlet Listener类 具体如下

   

  public class MyServlet extends javax.servlet.http.HttpServlet {

    @Override
protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        System.out.println("hello servlet  !!!");
        this.doPost(req, resp);
    }

    @Override
protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        resp.getWriter().println("hello Servlet!!");
    }
}

 

public class MyListener implements javax.servlet.ServletContextListener {

    @Override
public void contextInitialized(ServletContextEvent servletContextEvent) {
      System.out.println("contextInitialized...web容器启动!");
    }

    @Override
public void contextDestroyed(ServletContextEvent servletContextEvent) {
      System.out.println("contextDestroyed...web容器销毁");
    }
}

 

   public class MyFilter implements javax.servlet.Filter {

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

    }

    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
       System.out.println("filter拦截器进行了拦截...");
        filterChain.doFilter(servletRequest, servletResponse); // 注意这行代码
    }

    @Override
    public void destroy() {

    }
}

 

 

  2 编写springBoot配置类

  @Configuration

public class MyConfig {

   @Bean
public ServletRegistrationBean myServlet () {
       ServletRegistrationBean servletRegistrationBean = new ServletRegistrationBean(new MyServlet(), "/myServlet");
       servletRegistrationBean.addUrlMappings("/myServletTwo");
       servletRegistrationBean.setLoadOnStartup(1);
       return servletRegistrationBean;
   }

   @Bean
public FilterRegistrationBean myFilter () {
       FilterRegistrationBean filterRegistrationBean = new FilterRegistrationBean(new MyFilter());
       filterRegistrationBean.setUrlPatterns(Arrays.asList("/hello", "/myServlet"));
       return filterRegistrationBean;
   }

   @Bean
public ServletListenerRegistrationBean myListener () {
       ServletListenerRegistrationBean servletListenerRegistrationBean = new ServletListenerRegistrationBean(new MyListener());
       return servletListenerRegistrationBean;
   }

    @Bean  //一定要将这个定制器加入到容器中
public EmbeddedServletContainerCustomizer embeddedServletContainerCustomizer(){
        return new EmbeddedServletContainerCustomizer() {

            //定制嵌入式的Servlet容器相关的规则
@Override
public void customize(ConfigurableEmbeddedServletContainer container) {
                container.setPort(8083);
            }
        };
    }
}