spring mvc 下载文件

spring mvc如何下载文件呢?

spring mvc怎么下载图片呢?

有两种方式:

方式一:使用注解@ResponseBody

 

@ResponseBody
	@RequestMapping(value = "/download",produces="image/jpeg")
	public byte[] downloadFile(HttpServletRequest request, HttpServletResponse response,String contentType2,boolean isInline)
			throws IOException {
		byte[]bytes=FileUtils.getBytes4File("D:\\Temp\\cc.jpg");
//		response.addHeader("Content-Disposition", downloadType+";filename=\"a.jpg\"");
		WebServletUtil.setDownloadContentDisposition(isInline, "c.jpg", response);
		return bytes;

	}

 WebServletUtil.setDownloadContentDisposition 的实现如下:

 

 

/***
	 * spring MVC下载文件设置的Content-Disposition
	 * @param isInline
	 * @param fileName
	 * @return
	 */
	public static String getContentDisposition(boolean isInline,String fileName){
		String downloadType=null;
		if(isInline){
			downloadType=Constant2.CONTENT_DISPOSITION_INLINE;
		}else{
			downloadType=Constant2.CONTENT_DISPOSITION_ATTACHMENT;
		}
		if(ValueWidget.isNullOrEmpty(fileName)){
			fileName="name_not_specified";
		}
		String format=downloadType+";filename=\""+fileName+"\"";
		return format;
	}
	/***
	 * 下载文件(或内联显示)时设置Content-Disposition
	 * @param isInline
	 * @param fileName
	 * @param response
	 */
	public static void setDownloadContentDisposition(boolean isInline,String fileName, HttpServletResponse response){
		response.addHeader(Constant2.CONTENT_DISPOSITION, WebServletUtil.getContentDisposition(isInline, fileName));
	}

 注意:(1)一定要通过@RequestMapping注解的produces 设置response 的content type;

(2)设置应答头时要使用addHeader,而不是setHeader

 

方式二:使用ResponseEntity

@RequestMapping(value = "/download3")
    public ResponseEntity<byte[]> download() throws IOException {
        HttpHeaders headers = new HttpHeaders();
        headers.setContentType(MediaType.IMAGE_JPEG);
//        headers.setContentDispositionFormData("inline", "dict.jpg");//attachment
        headers.set(Constant2.CONTENT_DISPOSITION,WebServletUtil.getContentDisposition(true, "dict.jpg"));
        return new ResponseEntity<byte[]>(FileUtils.getBytes4File("D:\\Temp\\cc.jpg"),
                                          headers, HttpStatus.CREATED);
    }

/***
	 * favicon.ico 
	 * @throws IOException 
	 */
	@RequestMapping(value = "/favicon.ico")
	public ResponseEntity<byte[]> faviconIco(HttpServletRequest request) throws IOException {
		HttpHeaders headers = new HttpHeaders();
        headers.setContentType(MediaType.IMAGE_PNG);
        String faviconIcoName="sms-4.ico";
        headers.set(Constant2.CONTENT_DISPOSITION,WebServletUtil.getContentDisposition(true, faviconIcoName));
        ///home/whuang/software/apache-tomcat-7.0.53/webapps/ROOT/
        String webappPath=null;
        if(WebServletUtil.isLocalIp(request)){//服务器在本机(访问ip为127或localhost)
        	webappPath=WebServletUtil.getRealPath(request);
        }else{
        	webappPath=DictionaryParam.get(Constant2.DICTIONARY_GROUP_GLOBAL_SETTING, "WEB-INF_LOC");
        }
        return new ResponseEntity<byte[]>(FileUtils.getBytes4File(
        		webappPath
        		+"WEB-INF/static/img/"+faviconIcoName),
                                          headers, HttpStatus.CREATED);

	}

  

注意:不要使用headers.setContentDispositionFormData 来设置Content-Disposition

评论

4 楼 chen_lian 2016-02-18  

HttpStatus.CREATED 改为HttpStatus.OK 否则IE下面不好用

3 楼 chen_lian 2016-02-18  

楼主我给补充了一下 嘿嘿

2 楼 chen_lian 2016-02-18  

public class FileUtil {

	/**
	 * 读取二进制文件并且写入数组里
	 * @param filePath
	 * @return
	 * @throws IOException 
	 * @throws FileNotFoundException 
	 */
	public static byte[] getBytes4File(String filePath) throws IOException {

		InputStream in = null;
		BufferedInputStream buffer = null;
		DataInputStream dataIn = null;
		ByteArrayOutputStream bos = null;
		DataOutputStream dos = null;
		byte[] bArray = null;
		try {
			in = new FileInputStream(filePath);
			buffer = new BufferedInputStream(in);
			dataIn = new DataInputStream(buffer);
			bos = new ByteArrayOutputStream();
			dos = new DataOutputStream(bos);
			byte[] buf = new byte[1024];
			while (true) {
				int len = dataIn.read(buf);
				if (len < 0)
					break;
				dos.write(buf, 0, len);
			}
			bArray = bos.toByteArray();

		} catch (Exception e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
			return null;

		} finally {

			if (in != null)
				in.close();
			if (dataIn != null)
				dataIn.close();
			if (buffer != null)
				buffer.close();
			if (bos != null)
				bos.close();
			if (dos != null)
				dos.close();
		}

		return bArray;
	}
}

1 楼 chen_lian 2016-02-18  

FileUtils 这个类没有源码