SpringMVC学习笔记(六)

一.SpringMVC文件的上传

1.1.需要导入两个jar包

1.2在SpringMVC配置文件中加入

<!-- upload settings -->
<bean id="multipartResolver"  class="org.springframework.web.multipart.commons.CommonsMultipartResolver">
    <property name="maxUploadSize" value="102400000">
    <property name="defaultEncoding" value="utf-8">
</property>
</bean>

注意:bean的id必须有而且必须叫multipartResolver

1.3方法代码

@RequestMapping(value="/upload",method=RequestMethod.POST)
public String upload(HttpServletRequest req) throws Exception{
    MultipartHttpServletRequest mreq = (MultipartHttpServletRequest)req;
    MultipartFile file = mreq.getFile("file");
    String fileName = file.getOriginalFilename();
    SimpleDateFormat sdf = new SimpleDateFormat("yyyyMMddHHmmss");
    FileOutputStream fos = new FileOutputStream(req.getSession().getServletContext().getRealPath("/")+
            "upload/"+sdf.format(new Date())+fileName.substring(fileName.lastIndexOf('.')));
    fos.write(file.getBytes());
    fos.flush();
    fos.close();

    return "hello";
}

二. SpringMVC文件的下载.

2.1 准备下载源

　　在WebContent下新建files目录，放入aaa.txt，作为下载源

2.2 在index.jsp添加超链接作为下载入口

<a href="testResponseEntity" id="testJson">testResponseEntity</a><br/>

2.3 在handler SpringMVCTest中添加接口

@RequestMapping("testResponseEntity")
public ResponseEntity<byte[]> testResponseEntity(HttpSession session) throws IOException{
    byte[] body = null;
    ServletContext servletContext = session.getServletContext();
    InputStream in = servletContext.getResourceAsStream("/files/aaa.txt");
    body = new byte[in.available()];
    in.read(body);

    HttpHeaders headers = new HttpHeaders();
    headers.add("Content-Disposition", "attachment;filename=aaa.txt");
    HttpStatus statusCode = HttpStatus.OK;
    ResponseEntity<byte[]> response = new ResponseEntity<>(body, headers, statusCode);
    return response;
}