JAVA从数据库读取BLOB下载

[作妖的程序员]

@Path("/download")
	@POST
	@Produces(MediaType.APPLICATION_OCTET_STREAM)
	public Response download(@FormParam("tid") String tid) {
		List<NdsbQyjbxxDTO> list = ndsbBLOImpl.queryFileById(tid);
		NdsbQyjbxxDTO dto = list.get(0);
		String fjmc = dto.getFjmc();//附件名称
		byte fjnr[] = dto.getFjnr();//附件内容
		ResponseBuilder builder = Response.ok(fjnr, "application/x-download;charset=utf-8");
		try {
			builder.header("Content-Disposition", "attachment; filename=" + URLEncoder.encode(fjmc, "UTF-8") + "");
		} catch (UnsupportedEncodingException e) {
			e.printStackTrace();
		}
		Response response =builder.build();
		return response;
	}

下载的文件一直是1KB，打开显示如下：

[qybao]

你从数据库读出的是byte数组，应该用stream的形式来返回

@Path("/download")
    @POST
    @Produces(MediaType.APPLICATION_OCTET_STREAM)
    public Response download(@FormParam("tid") String tid) {
        List<NdsbQyjbxxDTO> list = ndsbBLOImpl.queryFileById(tid);
        NdsbQyjbxxDTO dto = list.get(0);
        String fjmc = dto.getFjmc();//附件名称
        byte fjnr[] = dto.getFjnr();//附件内容
        StreamingOutput stream = new StreamingOutput() { //实现stream
            @Override
            public void write(OutputStream output) throws IOException, WebApplicationException {
                try {
                    output.write(fjnr); //把数据库读出的字节输出到stream
                } catch (Exception e) {
                    throw new WebApplicationException(e);
                }
            }
        };
        //ResponseBuilder builder = Response.ok(fjnr, "application/x-download;charset=utf-8");
       ResponseBuilder builder = Response.ok(stream); //用stream返回
        try {
            builder.header("Content-Disposition", "attachment; filename=" + URLEncoder.encode(fjmc, "UTF-8") + "");
        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
        }
        Response response =builder.build();
        return response;
    }

[KeepSayingNo]

你要把你的文件写道这个对象里面，然后再返回吧 ByteArrayOutputStream outStream =new ByteArrayOutputStream();