更多的配置

配置DispatcherServlet

@Override    protected void customizeRegistration(ServletRegistration.Dynamic registration) {        registration.setMultipartConfig(                new MultipartConfigElement("./")        );    }

配置Servlet与Filter

@Override    public void onStartup(ServletContext servletContext) throws ServletException {        super.onStartup(servletContext);        var a=servletContext.addServlet("my-servlet",MyServlet.class);        a.addMapping("/my");        var b= servletContext.addFilter("my-fliter",MyFliter.class);        b.addMappingForUrlPatterns(null,false,"/*");    }

处理multipart 数据

必要前提

• form表单的enctype取值必须是：multipart/form-data
• method属性取值必须是Post
• 提供一个文件选择域``

使用

• 配置multipart解析器
  • StandardServletMultipartResolver
  • CommonsMultipartResolver

@Bean    public MultipartResolver multipartResolver(){        return new StandardServletMultipartResolver();    }

<bean id="multipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver"/>

• 处理multipart 请求

@RequestMapping("/upload")    @ResponseBody    public String upload(@RequestPart("file")MultipartFile file) throws IOException {        FileUtils.writeByteArrayToFile(new File("d:/"+file.getOriginalFilename()),file.getBytes());        return "上传完成";    }

<form action="./upload" enctype="multipart/form-data" method="post">    <input type="file" name="file">    <input type="submit"></form>

处理异常

• 自定义异常

@ResponseStatus(value = HttpStatus.NOT_FOUND,reason = "未找到")public class MyException extends RuntimeException{ }

@RequestMapping("/home")    public String hello(Model model){        model.addAttribute("time", LocalDate.now());        if (true)        throw new MyException();        return "home.html";    }

定义异常处理

public class MyExceptionHandler implements HandlerExceptionResolver {    @Override    public ModelAndView resolveException(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) {        try {            response.getWriter().println(ex.getMessage());        } catch (IOException e) {            e.printStackTrace();        }        return null;    }}

<bean id="handlerExceptionResolver" class="MyExceptionHandler"/>

• 异常处理器

@ExceptionHandler(Exception.class)@ResponseBodypublic Object handler(Exception e){    return e.getMessage();}

控制器通知

本质：对Controller进行AOP

// 所有的controller发生异常都会通过这个类进行处理@ControllerAdvicepublic class MyControllerAdvice {    @ExceptionHandler(Exception.class)    @ResponseBody    public Object handler(Exception e){        return e.getMessage();    }}

请求重定向转发数据

forward(服务器转发)与redirect(客户端重定向)

重定向传递数据的方法

• url传递
• flash属性传递

拦截器

public class MyInterceptor implements HandlerInterceptor {    @Override    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {        System.out.println("进入controller前执行");        return true;    }    @Override    public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {        System.out.println("完成controller方法后执行");    }    @Override    public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {        System.out.println("请求完成执行");    }}

    <mvc:interceptors>        <mvc:interceptor>            <mvc:mapping path="/**"/>            <bean class="wang.ismy.spring.mvc.MyInterceptor"/>        </mvc:interceptor>    </mvc:interceptors>