SpringBoot整合JavaWeb

1、SpringBoot整合Servlet的兩種方式

1.經過註解掃描完成Servlet組件的註冊

編寫Servlet

package com.example.demo.servlet; import java.io.IOException; import javax.servlet.ServletException; import javax.servlet.annotation.WebServlet; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; /** *SpringBoot整合Servlet方式一 * *<servlet> * <servlet-name>FirstServlet</servlet-name> * <servlet-class>com.bjsxt.servlet.FirstServlet</servlet-class> *</servlet> * *<servlet-mapping> * <servlet-name>FirstServlet</servlet-name> * <url-pattern>/first</url-pattern> *</servlet-mapping> * */ @WebServlet(name="FirstServlet",urlPatterns="/first") public class FirstServlet extends HttpServlet { /** * */
    private static final long serialVersionUID = 8500147337364528371L; @Override protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException { super.doGet(req, resp); System.out.println("FirstServlet..."); } }

編寫啓動器類

package com.example.demo; import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.SpringBootApplication; import org.springframework.boot.web.servlet.ServletComponentScan; @SpringBootApplication @ServletComponentScan //在springBoot啓動時會掃描@WebServlet，並將該類實例化
public class SpringbootWebApplication { public static void main(String[] args) { SpringApplication.run(SpringbootWebApplication.class, args); } }

2.經過方法完成Servlet組件的註冊

編寫Servlet

package com.example.demo.servlet; import java.io.IOException; import javax.servlet.ServletException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; /** *SpringBoot整合Servlet方式二 * */

public class SecondServlet extends HttpServlet { /** * */
    private static final long serialVersionUID = -7076398985231616781L; @Override protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException { System.out.println("SecondServlet..."); } }

編寫啓動器類

package com.example.demo; import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.SpringBootApplication; import org.springframework.boot.web.servlet.ServletRegistrationBean; import org.springframework.context.annotation.Bean; import com.example.demo.servlet.SecondServlet; /** * SpringBoot整合Servlet方式二 * * */ @SpringBootApplication public class App2 { public static void main(String[] args) { SpringApplication.run(App2.class, args); } @Bean public ServletRegistrationBean getServletRegistrationBean(){ ServletRegistrationBean bean = new ServletRegistrationBean(new SecondServlet()); bean.addUrlMappings("/second"); return bean; } }

2、SpringBoot整合Filter的兩種方式

1.經過註解掃描完成Filter組件的註冊

編寫Filter

/** *SpringBoot整合Filter 方式一 *<filter> * <filter-name>FirstFilter</filter-name> * <filter-class>com.bjsxt.filter.FirstFilter</filter-class> *</filter> *<filter-mapping> * <filter-name>FirstFilter</filter-name> * <url-pattern>/first</url-pattern> *</filter-mapping> */
//@WebFilter(filterName="FirstFilter",urlPatterns={"*.do","*.jsp"})
@WebFilter(filterName="FirstFilter",urlPatterns="/first") public class FirstFilter implements Filter { @Override public void destroy() { // TODO Auto-generated method stub
 } @Override public void doFilter(ServletRequest arg0, ServletResponse arg1, FilterChain arg2) throws IOException, ServletException { System.out.println("進入Filter"); arg2.doFilter(arg0, arg1); System.out.println("離開Filter"); } @Override public void init(FilterConfig arg0) throws ServletException { // TODO Auto-generated method stub
 } }

編寫啓動類

/** *SpringBoot整合Filter 方式一 * */ @SpringBootApplication @ServletComponentScan public class App3 { public static void main(String[] args) { SpringApplication.run(App3.class, args); } }

2.經過方法完成Filter組件的註冊

編寫Filter

/** * *SpringBoot整合Filter 方式二 * */
public class SecondFilter implements Filter { @Override public void destroy() { // TODO Auto-generated method stub
 } @Override public void doFilter(ServletRequest arg0, ServletResponse arg1, FilterChain arg2) throws IOException, ServletException { System.out.println("進入SecondFilter"); arg2.doFilter(arg0, arg1); System.out.println("離開SecondFilter"); } @Override public void init(FilterConfig arg0) throws ServletException { // TODO Auto-generated method stub
 } }

 

編寫啓動器類

/** * SpringBoot整合Filter方式二 * * */ @SpringBootApplication public class App4 { public static void main(String[] args) { SpringApplication.run(App4.class, args); }/** * 註冊Filter */ @Bean public FilterRegistrationBean getFilterRegistrationBean(){ FilterRegistrationBean bean = new FilterRegistrationBean(new SecondFilter()); //bean.addUrlPatterns(new String[]{"*.do","*.jsp"});
        bean.addUrlPatterns("/second"); return bean; } }

3、SpringBoot整合Listener的兩種方式

1.經過註解掃描完成Listener的註冊

編寫Listener

/** * springBoot整合Listener * *<listener> * <listener-class>com.bjsxt.listener.FirstListener</listener-class> *</listener> */ @WebListener public class FirstListener implements ServletContextListener { @Override public void contextDestroyed(ServletContextEvent arg0) { // TODO Auto-generated method stub
 } @Override public void contextInitialized(ServletContextEvent arg0) { System.out.println("Listener...init......"); } }

編寫啓動器

/** * springBoot整合Listener方式一 * * */ @SpringBootApplication @ServletComponentScan public class App5 { public static void main(String[] args) { SpringApplication.run(App5.class, args); } }

2.  經過方法完成Listener組件註冊

編寫Listener

/** * springBoot整合Listener方式二。 * * */
public class SecondListener implements ServletContextListener { @Override public void contextDestroyed(ServletContextEvent arg0) { // TODO Auto-generated method stub
 } @Override public void contextInitialized(ServletContextEvent arg0) { System.out.println("SecondListener..init....."); } }

 

編寫啓動器類

/** * SpringBoot整合Listener方式二 * * */ @SpringBootApplication public class App6 { public static void main(String[] args) { SpringApplication.run(App6.class, args); } /** * 註冊listener */ @Bean public ServletListenerRegistrationBean<SecondListener> getServletListenerRegistrationBean(){ ServletListenerRegistrationBean<SecondListener> bean= new ServletListenerRegistrationBean<SecondListener>(new SecondListener()); return bean; } }

4、訪問靜態資源

1. SpringBoot可在classpath/static的目錄下存放靜態資源

2. SpringBoot可在ServletContext根目錄下存放靜態資源

在src/main/webapp  目錄名稱必需要webapp

5、文件上傳

1.編寫Controller類

/** * SpringBoot文件上傳 * * */
//@Controller
@RestController //表示該類下的方法的返回值會自動作json格式的轉換
public class FileUploadController { /* * 處理文件上傳 */ @RequestMapping("/fileUploadController") public Map<String, Object> fileUpload(MultipartFile filename)throws Exception{ System.out.println(filename.getOriginalFilename()); filename.transferTo(new File("d:/"+filename.getOriginalFilename())); Map<String, Object> map = new HashMap<>(); map.put("msg", "ok"); return map; } }

 

2.編寫啓動器類

/** * SpringBoot文件上傳 * * */ @SpringBootApplication public class App7 { public static void main(String[] args) { SpringApplication.run(App7.class, args); } }

3.編寫application.properties配置文件，設置上傳文件大小的默認值

spring.servlet.multipart.max-file-size=200MB spring.servlet.multipart.max-request-size=200MB

設置單個上傳文件的大小：spring.servlet.multipart.max-file-size=200MB 

設置一次請求上傳文件的總容量：spring.servlet.multipart.max-request-size=200MB

總結

本篇簡單介紹了SpringBoot整合Servlet、Filter、Listener、以及SpringBoot上傳文件的方式，下一篇將介紹SpringBoot視圖層技術。