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;

}