第一次写这么多逻辑在内的小功能

public long getByUser(final TimesheetDO timesheetDo, final Integer userId) {
		long sum =  0;
		boolean isExist = false;           //用于分别是否为新添加的还是更新
		boolean flag = false;
		@SuppressWarnings("unchecked")
		final List<TimesheetDO> list = getHibernateTemplate().find(
				"from TimesheetDO t");
		//如果id已经存在，则减去原来的，加上现在的，
		//如果不存在，则直接加上现在的
		if (list != null && list.size() > 0) {
			for (final TimesheetDO sheet: list) {
				isExist = false;
				sum += sheet.getDuration();
				isExist = sheet.getId().equals(timesheetDo.getId());

				if ( isExist == true  ){
					flag = true;
					final long temp = sheet.getDuration();
					//System.out.println("\n\n\n" + temp + "\n\n\n");
					sum = sum - temp;
					//System.out.println("\n\n\n" + sum + "\n\n\n");
					sum += timesheetDo.getDuration();
					//System.out.println("\n\n\n" + sum + "\n\n\n");
				}


			}
		}

		//如果id不存在，则最后一个需要加上去，再进行判断
		if ( flag == false ){
			sum += timesheetDo.getDuration();
		}
		//System.out.println("\n\n\n" + sum + "\n\n\n");
		return sum;

	}

纪念一下自己。。。。。要多多加油。。。。

继续修改，修改成功，并且感觉写的还是蛮优美的：

public long getByUser(final TimesheetDO timesheetDo, final Integer userId) {
		long sum =  0;
		boolean isExist = false;           //用于分别是否为新添加的还是更新
		boolean flag = false;
		//System.out.println("\n\n\n" + timesheetDo.getStartTime().toString().substring(0, 10) + "\n\n\n");
		@SuppressWarnings("unchecked")
		//final List<TimesheetDO> list = getHibernateTemplate().find(
		//"from TimesheetDO t");
		final List<TimesheetDO> list = getHibernateTemplate().find(
				"from TimesheetDO t where t.user.id= ? and substr(t.startTime, 1, 10) = ?",
				new Object[]{userId, timesheetDo.getStartTime().toString().substring(0, 10)});
		//如果id已经存在，则减去原来的，加上现在的，
		//如果不存在，则直接加上现在的
		if (list != null && list.size() > 0) {
			for (final TimesheetDO sheet: list) {
				isExist = false;
				sum += sheet.getDuration();
				isExist = sheet.getId().equals(timesheetDo.getId());

				if ( isExist == true  ){
					flag = true;
					final long temp = sheet.getDuration();
					//System.out.println("\n\n\n" + temp + "\n\n\n");
					sum = sum - temp;
					//System.out.println("\n\n\n" + sum + "\n\n\n");
					sum += timesheetDo.getDuration();
					//System.out.println("\n\n\n" + sum + "\n\n\n");
				}


			}
		}

		//如果id不存在，则最后一个需要加上去，再进行判断
		if ( flag == false ){
			sum += timesheetDo.getDuration();
		}
		//System.out.println("\n\n\n" + sum + "\n\n\n");
		return sum;

	}

加油！！