spring笔记4 spring MVC的基础知识4

//todo

5，spring MVC的本地化解析，文件上传，静态资源处理，拦截器，异常处理等

spring MVC 默认使用AcceptHeaderLocalResolver,根据报文头的Accept-Language参数来确定本地化类型；

此外还可以使用CookieLocalResolver和SessionLocalResolver,如果想从每次请求的参数中获取本次请求对应的本地化类型，采用LocalChangerIntercepter拦截器；

有空写个实现国际化的实例...

spring实现文件上传相当简单，首先引入依赖包，common-upload ,common-io包，然后定义个MultipartResolver解析器，写个表单就可实现；这里给个例子：

 <!--文件上传依赖包-->
        <dependency>
            <groupId>commons-fileupload</groupId>
            <artifactId>commons-fileupload</artifactId>
            <version>1.3</version>
        </dependency>

<bean id="multipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver">
        <property name="defaultEncoding" value="UTF-8"/>
        <property name="maxUploadSize" value="2097152"/>
        <property name="uploadTempDir" value="temp"/>

    </bean>

<form action="/upload" enctype="multipart/form-data" method="post">


    <input type="file" name="file"/>

    <input type="submit">

</form>

    @RequestMapping(value = "/upload")
    public String uploadImg(@RequestParam("file")MultipartFile file){

          if(null!=file)
          {
              File newFile=new File("E://aaa.jpg");
              try {
                  file.transferTo(newFile);
              } catch (IOException e) {
                  e.printStackTrace();  //To change body of catch statement use File | Settings | File Templates.
              }
          }

        return "redirect:/account/list";
    }

结果是在E盘看到了一个上传的aaa.jpg图片；

静态资源的处理：在spring mvc的配置文件当中加上如下的配置，同时用默认的资源处理器和spring mvc自带的资源处置方式；

<mvc:default-servlet-handler/>

<mvc:resources mapping="/ftp/**" location="/resource/"/>

还可以在一个类中增加版本号的形式改变mapping的名称；

装配拦截器：

<mvc:interceptors>
<mvc:interceptor>
<mvc:mapping path="/account/*"/>
<bean class="com.lfc.sh.web.sp.framework.intercepter.LoginIntercepter"></bean>
</mvc:interceptor>
</mvc:interceptors>

package com.lfc.sh.web.sp.framework.intercepter;

import org.apache.log4j.Logger;
import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

/**
 * Company: Copyright© 2009 www.7road.com All rights reserved.
 * com.lfc.sh.web.sp.framework.intercepter
 * Create Date: 13-11-19 下午5:47
 * Note:  登录的拦截器
 */
public class LoginIntercepter implements HandlerInterceptor {

    private static Logger logger = Logger.getLogger(LoginIntercepter.class);

    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {



       logger.warn("进入登录拦截器的preHandle方法"+" url:"+ request.getRequestURI());
        return true;
    }

    @Override
    public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {
        logger.warn("进入登录拦截器的postHandle方法");
    }

    @Override
    public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {
        logger.warn("进入登录拦截器的afterCompletion方法");
    }
}

下面是日志：

2013-11-19 18:00:16 com.lfc.sh.web.sp.framework.intercepter.LoginIntercepter.preHandle(26)---[160013]
[WARN] 进入登录拦截器的preHandle方法 url:/account/create
2013-11-19 18:00:16 com.lfc.sh.web.sp.framework.intercepter.LoginIntercepter.postHandle(32)---[160015]
[WARN] 进入登录拦截器的postHandle方法
2013-11-19 18:00:16 com.lfc.sh.web.sp.framework.intercepter.LoginIntercepter.afterCompletion(37)---[160028]
[WARN] 进入登录拦截器的afterCompletion方法

异常处理：

spring Mvc 通过HandlerExceptionResolver处理程序的异常；

接口的功能见截图：