SpringBoot 中使用自定义的 Servlet, Filter, Listener-白红宇

SpringBoot 中使用自定义的 Servlet, Filter, Listener

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发布时间：2019-06-25

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SpringBoot 中使用自定义的 Servlet, Filter, Listener 有两种方式

1. 使用 @ServletComponentScan 定义要扫描的包目录, Servlet, Filter, Listener 可以通过 @WebServlet, @WebListener, @WebFilter 进行自动注册.

@Controller@SpringBootApplication@ComponentScan(basePackages={"com.codingos.demo","com.codingos.springbootlession1"})@ServletComponentScan(basePackages="com.codingos.springbootlession1.demo")public class SpringBootLession1Application {    public static void main(String[] args) {		SpringApplication.run(SpringBootLession1Application.class, args);	}}

@WebServlet(name="servletDemo", urlPatterns="/servletDemo", initParams= {@WebInitParam(name="myname",value="myvalue")})public class ServletDemo extends HttpServlet {@WebFilter(servletNames="servletDemo")public class FilterDemo extends OncePerRequestFilter {@WebListenerpublic class RequestListenerDemo implements ServletRequestListener {

2. 自定义一些 Servlet, Filter, Listener, 然后在 Application 类中使用进行注册

package com.codingos.springbootlession1;import java.util.EventListener;import java.util.HashMap;import java.util.Map;import org.springframework.beans.factory.annotation.Autowired;import org.springframework.boot.SpringApplication;import org.springframework.boot.autoconfigure.SpringBootApplication;import org.springframework.boot.web.servlet.FilterRegistrationBean;import org.springframework.boot.web.servlet.ServletComponentScan;import org.springframework.boot.web.servlet.ServletListenerRegistrationBean;import org.springframework.boot.web.servlet.ServletRegistrationBean;import org.springframework.context.annotation.Bean;import org.springframework.context.annotation.ComponentScan;import org.springframework.data.redis.core.StringRedisTemplate;import org.springframework.stereotype.Controller;import org.springframework.web.bind.annotation.RequestMapping;import org.springframework.web.bind.annotation.ResponseBody;import com.codingos.springbootlession1.demo.FilterDemo2;import com.codingos.springbootlession1.demo.RequestListenerDemo2;import com.codingos.springbootlession1.demo.ServletDemo2;@Controller@SpringBootApplication@ComponentScan(basePackages={"com.codingos.demo","com.codingos.springbootlession1"})@ServletComponentScan(basePackages="com.codingos.springbootlession1.demo")public class SpringBootLession1Application {		@Autowired	private StringRedisTemplate template;		public static void main(String[] args) {		SpringApplication.run(SpringBootLession1Application.class, args);	}	@Bean	public static ServletRegistrationBean servletRegistrationBean() {		ServletRegistrationBean servletRegistrationBean = new ServletRegistrationBean();		servletRegistrationBean.setServlet(new ServletDemo2());		servletRegistrationBean.setName("servletDemo2");		servletRegistrationBean.addUrlMappings("/spring-boot/servletDemo2");		servletRegistrationBean.addInitParameter("myname", "myvalue");		return servletRegistrationBean;	}		@Bean	public static FilterRegistrationBean filterRegistrationBean() {		FilterRegistrationBean filterRegistrationBean = new FilterRegistrationBean();		filterRegistrationBean.setFilter(new FilterDemo2());		filterRegistrationBean.addServletNames("servletDemo2");		return filterRegistrationBean;	}		@Bean	public static ServletListenerRegistrationBean
    
      ServletListenerRegistrationBean() {		ServletListenerRegistrationBean
     
       servletListenerRegistrationBean = new ServletListenerRegistrationBean<>();		servletListenerRegistrationBean.setListener(new RequestListenerDemo2());		return servletListenerRegistrationBean;	}}

package com.codingos.springbootlession1.demo;import java.io.IOException;import java.io.Writer;import javax.servlet.ServletConfig;import javax.servlet.ServletException;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;public class ServletDemo2 extends HttpServlet {	private static final long serialVersionUID = 4982760566703313419L;		private String value;	@Override	public void init(ServletConfig config) throws ServletException {		value = config.getInitParameter("myname");		super.init(config);	}		@Override	protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {		Writer writer = resp.getWriter();		req.getServletContext().log("ServletDemo2 doGet");		writer.write("ServletDemo2 AAAAAAA "+ value +"");		//super.doGet(req, resp);	}}

package com.codingos.springbootlession1.demo;import java.io.IOException;import javax.servlet.FilterChain;import javax.servlet.ServletContext;import javax.servlet.ServletException;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import org.springframework.web.filter.OncePerRequestFilter;public class FilterDemo2 extends OncePerRequestFilter {	@Override	protected void doFilterInternal(HttpServletRequest request, HttpServletResponse response, FilterChain filterChain)			throws ServletException, IOException {		ServletContext servletContext = request.getServletContext();		servletContext = getServletContext();//		servletContext.log("servletDemo2 was filtered");		servletContext.log(request.getRequestURI() + "servletDemo2 was filtered");		filterChain.doFilter(request, response);	}}

package com.codingos.springbootlession1.demo;import javax.servlet.ServletContext;import javax.servlet.ServletRequestEvent;import javax.servlet.ServletRequestListener;public class RequestListenerDemo2 implements ServletRequestListener {	@Override	public void requestInitialized(ServletRequestEvent sre) {//		HttpServletRequest request = (HttpServletRequest) sre.getServletRequest();//		ServletContext servletContext = request.getServletContext();		ServletContext servletContext = sre.getServletContext();		servletContext.log("************ RequestListenerDemo2 requestInitialized ******");	}		@Override	public void requestDestroyed(ServletRequestEvent sre) {		ServletContext servletContext = sre.getServletContext();		servletContext.log("************ RequestListenerDemo2 requestDestroyed ******");	}}

Filter 链的执行顺序