中央轉發器（DispatcherServlet）
控制器
視圖解析器
靜態資源訪問
消息轉換器
格式化
靜態資源管理
?
一、中央轉發器
Xml無需配置
<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> |
中央轉發器被springboot自動接管，不再需要我們在web.xml中配置，我們現在的項目也不是web項目，也不存在web.xml,
org.springframework.boot.autoconfigure.web.servlet.DispatcherServletAutoConfiguration,
?控制器
控制器Controller在springboot的注解掃描范圍內自動管理。
視圖解析器自動管理
Inclusion of ContentNegotiatingViewResolver and BeanNameViewResolver beans.
ContentNegotiatingViewResolver：組合所有的視圖解析器的；
?曾經的配置文件無需再配
?
<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> |
?源碼：
public ContentNegotiatingViewResolver viewResolver(BeanFactory beanFactory) {
ContentNegotiatingViewResolver resolver = new ContentNegotiatingViewResolver();
resolver.setContentNegotiationManager((ContentNegotiationManager)beanFactory.getBean(ContentNegotiationManager.class));
resolver.setOrder(-2147483648);
return resolver;
} |
當我們做文件上傳的時候我們也會發現multipartResolver是自動被配置好的頁面
?
<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();
} |
文件上傳大小可以通過配置來修改
打開application.properties, 默認限制是10MB，我們可以任意修改
@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();
} |
文件上傳大小可以通過配置來修改
打開application.properties, 默認限制是10MB，我們可以任意修改
二、消息轉換和格式化
?Springboot自動配置了消息轉換器
格式化轉換器的自動注冊?
時間類型我們可以在這里修改?
在配置文件中指定好時間的模式我們就可以輸入了?
?三、springboot自動擴展SpringMVC
在實際開發中springboot并非完全自動化，很多跟業務相關我們需要自己擴展，springboot給我提供了接口。
我們可以來通過實現WebMvcConfigurer接口來擴展
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 在容器中注冊視圖控制器（請求轉發）?
創建一個MyMVCCofnig實現WebMvcConfigurer接口，實現一下addViewControllers方法，我們完成通過/tx訪問，轉發到success.html的工作
@Configuration
public class MyMVCCofnig implements WebMvcConfigurer{
@Override
public void addViewControllers(ViewControllerRegistry registry) {
registry.addViewController("/tx").setViewName("success");
}
}
3.2 注冊格式化
?用來可以對請求過來的日期格式化的字符串來做定制化。當然通過application.properties配置也可以辦到。
@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 消息轉換器擴展fastjson
?在pom.xml中引入fastjson
<dependency>
?? <groupId>com.alibaba</groupId>
?? <artifactId>fastjson</artifactId>
?? <version>1.2.47</version>
</dependency> |
配置消息轉換器，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);
} |
在實體類上可以繼續控制?
public class User{private? String username;private? String password;private int age;private int score;private int gender;@JSONField(format = "yyyy-MM-dd")private Date date; |
?3.4 攔截器注冊
1.創建攔截器
public class MyInterceptor implements HandlerInterceptor {
@Override
public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
System.out.println("前置攔截");
return true;
}
@Override
public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {
System.out.println("后置攔截");
}
@Override
public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {
System.out.println("最終攔截");
}
} |
2. 攔截器注冊
?
@Override
public void addInterceptors(InterceptorRegistry registry) {
registry.addInterceptor(new MyInterceptor())
.addPathPatterns("/**")
.excludePathPatterns("/hello2");
} |
并且推送至nexus私有依賴倉庫（筆記）)
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