SpringBoot 中Servlet,Filter,Listener的代码配置

SpringBoot创建web项目中,有可能是以jar的方式创建的.创建之后没有对应的webapp目录,也没有对应的web.xml文件.而web.xml文件通常会配置Servlet,Filter,Listener等信息.SpringBoot为我们提供了ServletRegistrationBean,FilterRegistrationBean,ServletListenerRegistrationBean等类配置相关信息.
1.Servlet配置
1)新建servlet类

public class MyServlet extends HttpServlet{


    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        doPost(req, resp);
    }

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

2)通过ServletRegistrationBean注册

   /**
     * 注入servlet   代替web.xml配置
     * @return
     */
    @Bean
    public ServletRegistrationBean servletRegistrationBean(){
        return new ServletRegistrationBean(new MyServlet(), "/myServlet");
    }

3)页面显示:

2.Filter配置
1)新建Filter类

package com.oxx.springboot.component;


import javax.servlet.*;
import java.io.IOException;

public class MyFilter implements Filter {
    @Override
    public void init(FilterConfig filterConfig) throws ServletException {
        System.out.println("-----myfilter  init......");
    }

    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        System.out.println("----------myfilter  doFilter.......");
        filterChain.doFilter(servletRequest, servletResponse);
    }

    @Override
    public void destroy() {
        System.out.println("------------myFilter  destroy........");
    }
}

2)通过FilterRegistrationBean注册:

/**
     * 注入filter   代替web.xml配置
     * @return
     */
    @Bean
    public FilterRegistrationBean filterRegistrationBean(){
        return new FilterRegistrationBean(new MyFilter(), servletRegistrationBean());
    }

3)启动项目,退出项目 控制台显示:

配置的是自定义的servlet,过滤的是/myServlet,需要访问一次才会出现doFilter…点击红色框框按钮退出才会显示destroy

3.Listener配置
1)新建Listener类:

import javax.servlet.ServletContextEvent;
import javax.servlet.ServletContextListener;

public class MyServletContextListener implements ServletContextListener{

    @Override
    public void contextInitialized(ServletContextEvent sce) {
        System.out.println("-----------------MyServletContextListener  init ......");
    }

    @Override
    public void contextDestroyed(ServletContextEvent sce) {
        System.out.println("---------------MyServletContextListener  destroy........");
    }
}

2)通过ServletListenerRegistrationBean注册Listener:

 /**
     * 注入listener  代替web.xml配置
     * @return
     */
    @Bean
    public ServletListenerRegistrationBean servletListenerRegistrationBean(){
        return new ServletListenerRegistrationBean(new MyServletContextListener());
    }

3)启动项目,退出项目 控制台显示

点击红色框框按钮退出,才回显示destroy…

4.容器相关配置
1)通过代码配置容器相关信息

  /**
     * 代码配置容器相关信息
     * @return
     */
    @Bean
    public WebServerFactoryCustomizer<TomcatServletWebServerFactory> webServerFactoryCustomizer(){
        return new WebServerFactoryCustomizer<TomcatServletWebServerFactory>() {
            @Override
            public void customize(TomcatServletWebServerFactory factory) {
                factory.setPort(9999);  //端口
                factory.setContextPath("/tomcat");  //访问路径
            }
        };
    }

2)启动项目 控制台显示:

本文地址：https://blog.csdn.net/xindanding/article/details/112002993