Object转Instant

String createTime = (picturepackage.get("createDate")).toString();
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
Date date = sdf.parse(createTime);
mediaPackageDTO.setCreateDate(date.toInstant());
或
commentDTO.setCommentDate(Instant.ofEpochMilli(    (      (Date) commentMap.get("create_date")     ).getTime()   ));

其中commentDTO.setCommentDate和mediaPackageDTO.setCreateDate这两个是Intant