java 关于时间

/**
 * 是否连续签到(true连续、false未连续)，今天和昨天比较 判断yesterday 是否是昨天的时间，true表示是昨天
 *
 * @param uid
 * @return
 */
public boolean ifSignedContinuous(Long uid){
    boolean flag = false;
    try{
        User user = appUserMapper.selectByPrimaryKey(uid);
        if(user != null){
            if(user.getSignLastTime() != null){
                SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
                String todayStr  = sdf.format(new Date()).toString();
                Date today = sdf.parse(todayStr);
                String yesterdayStr = sdf.format(user.getSignLastTime()).toString();
                Date yesterday = sdf.parse(yesterdayStr);
                if((today.getTime()-yesterday.getTime())>0 && (today.getTime()-yesterday.getTime())<=86400000) {
                    return true;
                }
            }
        }
    }catch (Exception e){
    }
    return flag;
}

 

/**
* 判断1个时间 是否是今天 
*/
for(Obj bean :list){
    SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
    String today = sdf.format(new Date()).toString();
    String createTime = sdf.format(bean.getCreateTime()).toString();
    if(today.equals(createTime)){
        flag = true;
        break;
    }
}