中央转发器（DispatcherServlet）
控制器
视图解析器
静态资源访问
消息转换器
格式化
静态资源管理
一、中央转发器
Xml无需配置
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| <servlet > <servlet-name >chapter2</servlet-name > <servlet-class >org.springframework.web.servlet.DispatcherServlet</servlet-class > <load-on-startup >1</load-on-startup > </servlet > <servlet-mapping > <servlet-name >chapter2</servlet-name > <url-pattern >/</url-pattern > </servlet-mapping > |
中央转发器被springboot自动接管，不再需要我们在web.xml中配置，我们现在的项目也不是web项目，也不存在web.xml,
org.springframework.boot.autoconfigure.web.servlet.DispatcherServletAutoConfiguration,
控制器
控制器Controller在springboot的注解扫描范围内自动管理。
视图解析器自动管理
Inclusion of ContentNegotiatingViewResolver and BeanNameViewResolver beans.
ContentNegotiatingViewResolver：组合所有的视图解析器的；
曾经的配置文件无需再配
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| <bean id ="de" class ="org.springframework.web.servlet.view.InternalResourceViewResolver" > <property name ="prefix" value ="/WEB-INF/jsp/" ></property > <property name ="suffix" value ="*.jsp" ></property > </bean > |
源码：
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| public ContentNegotiatingViewResolver viewResolver(BeanFactory beanFactory) { ContentNegotiatingViewResolver resolver = new ContentNegotiatingViewResolver(); resolver.setContentNegotiationManager((ContentNegotiationManager)beanFactory.getBean(ContentNegotiationManager.class )); resolver.setOrder(-2147483648); return resolver; } |
当我们做文件上传的时候我们也会发现multipartResolver是自动被配置好的页面|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| <form action= "/upload" method= "post" enctype= "multipart/form-data" > <input name= "pic" type= "file" > <input type= "submit" > </form > |
Controller|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| @ResponseBody @RequestMapping("/upload" ) public String upload(@RequestParam("pic" )MultipartFile file, HttpServletRequest request){ String contentType = file.getContentType(); String fileName = file.getOriginalFilename(); /*System.out.println("fileName-->" + fileName); System.out.println("getContentType-->" + contentType);*/ //String filePath = request.getSession().getServletContext().getRealPath("imgupload/"); String filePath = "D:/imgup/" ; try { this .uploadFile (file.getBytes(), filePath, fileName); } catch (Exception e) { // TODO: handle exception } return "success" ; } public static void uploadFile(byte [] file, String filePath, String fileName) throws Exception { File targetFile = new File(filePath); if (!targetFile.exists()){ targetFile.mkdirs(); } FileOutputStream out = new FileOutputStream(filePath+fileName); out.write(file); out.flush(); out.close(); } |
文件上传大小可以通过配置来修改打开application.properties, 默认限制是10MB，我们可以任意修改|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| @ResponseBody @RequestMapping("/upload" ) public String upload(@RequestParam("pic" )MultipartFile file, HttpServletRequest request){ String contentType = file.getContentType(); String fileName = file.getOriginalFilename(); /*System.out.println("fileName-->" + fileName); System.out.println("getContentType-->" + contentType);*/ //String filePath = request.getSession().getServletContext().getRealPath("imgupload/"); String filePath = "D:/imgup/" ; try { this .uploadFile (file.getBytes(), filePath, fileName); } catch (Exception e) { // TODO: handle exception } return "success" ; } public static void uploadFile(byte [] file, String filePath, String fileName) throws Exception { File targetFile = new File(filePath); if (!targetFile.exists()){ targetFile.mkdirs(); } FileOutputStream out = new FileOutputStream(filePath+fileName); out.write(file); out.flush(); out.close(); } |
文件上传大小可以通过配置来修改打开application.properties, 默认限制是10MB，我们可以任意修改
二、消息转换和格式化
Springboot自动配置了消息转换器
格式化转换器的自动注册
时间类型我们可以在这里修改
在配置文件中指定好时间的模式我们就可以输入了
三、springboot自动扩展SpringMVC
在实际开发中springboot并非完全自动化，很多跟业务相关我们需要自己扩展，springboot给我提供了接口。
我们可以来通过实现WebMvcConfigurer接口来扩展|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| public interface WebMvcConfigurer { default void configurePathMatch(PathMatchConfigurer configurer) { } default void configureContentNegotiation(ContentNegotiationConfigurer configurer) { } default void configureAsyncSupport(AsyncSupportConfigurer configurer) { } default void configureDefaultServletHandling(DefaultServletHandlerConfigurer configurer) { } default void addFormatters(FormatterRegistry registry) { } default void addInterceptors(InterceptorRegistry registry) { } default void addResourceHandlers(ResourceHandlerRegistry registry) { } default void addCorsMappings(CorsRegistry registry) { } default void addViewControllers(ViewControllerRegistry registry) { } default void configureViewResolvers(ViewResolverRegistry registry) { } default void addArgumentResolvers(List<HandlerMethodArgumentResolver> resolvers) { } default void addReturnValueHandlers(List<HandlerMethodReturnValueHandler> handlers) { } default void configureMessageConverters(List<HttpMessageConverter<?>> converters) { } default void extendMessageConverters(List<HttpMessageConverter<?>> converters) { } default void configureHandlerExceptionResolvers(List<HandlerExceptionResolver> resolvers) { } default void extendHandlerExceptionResolvers(List<HandlerExceptionResolver> resolvers) { } @Nullable default Validator getValidator() { return null ; } @Nullable default MessageCodesResolver getMessageCodesResolver() { return null ; } } |
3.1 在容器中注册视图控制器（请求转发）
创建一个MyMVCCofnig实现WebMvcConfigurer接口，实现一下addViewControllers方法，我们完成通过/tx访问，转发到success.html的工作
@Configuration
public class MyMVCCofnig implements WebMvcConfigurer{
@Override
public void addViewControllers(ViewControllerRegistry registry) {
registry.addViewController("/tx" ).setViewName("success" );
}
}
3.2 注册格式化
用来可以对请求过来的日期格式化的字符串来做定制化。当然通过application.properties配置也可以办到。
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| @Override public void addFormatters(FormatterRegistry registry) { registry.addFormatter(new Formatter<Date>() { @Override public String print(Date date, Locale locale) { return null ; } @Override public Date parse(String s, Locale locale) throws ParseException { return new SimpleDateFormat("yyyy-MM-dd" ).parse(s); } }); } |
3.3 消息转换器扩展fastjson
在pom.xml中引入fastjson
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| <dependency > <groupId >com.alibaba</groupId > <artifactId >fastjson</artifactId > <version >1.2.47</version > </dependency > |
配置消息转换器，添加fastjson
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| @Override public void configureMessageConverters(List<HttpMessageConverter<?>> converters) { FastJsonHttpMessageConverter fc = new FastJsonHttpMessageConverter(); FastJsonConfig fastJsonConfig = new FastJsonConfig(); fastJsonConfig.setSerializerFeatures(SerializerFeature.PrettyFormat ); fc.setFastJsonConfig(fastJsonConfig); converters.add(fc); } |
在实体类上可以继续控制
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| public classUser { privateString username; privateString password; private intage; private intscore; private intgender; @JSONField(format = "yyyy-MM-dd") privateDate date; |
3.4 拦截器注册
1.创建拦截器
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| public class MyInterceptor implements HandlerInterceptor { @Override public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception { System.out .println(" 前置拦截 " ); return true ; } @Override public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception { System.out .println(" 后置拦截 " ); } @Override public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception { System.out .println(" 最终拦截 " ); } } |
- 拦截器注册
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| @Override public void addInterceptors(InterceptorRegistry registry) { registry.addInterceptor(new MyInterceptor()) .addPathPatterns("/**" ) .excludePathPatterns("/hello2" ); } |