Java 空指针异常 Calendar.setTime
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Null Pointer Exception Calendar.setTime
提问by BVdjV
Calendar lastEditDate = Calendar.getInstance();
lastEditDate.setTime(rs.getDate("LAST_EDIT_DATE"));
productGroup.setLastEditDate(lastEditDate);
I've got a NullPointerException:
我有一个空指针异常：
[ERROR] [16.08.2013 11:30:43] [ DatabaseWorker] = [admin][Get product groups]
java.lang.NullPointerException
at java.util.Calendar.setTime(Calendar.java:1106)
at ro.gs.service.catering.dao.ProductGroupDAO.doWork(ProductGroupDAO.java:220)
Can somebody tell me why have I got this exception?
有人能告诉我为什么我有这个例外吗？
采纳答案by Qwerky
getDate(String columnLabel)returns
the column value; if the value is SQL NULL, the value returned is null
列值；如果值为 SQL NULL，则返回值为 null
Does your table allow nulls in this column?
您的表是否允许此列中出现空值？
回答by Ruchira Gayan Ranaweera
Because
因为
lastEditDate.setTime(rs.getDate("LAST_EDIT_DATE"));
In here rs.getDate("LAST_EDIT_DATE")is null
这里rs.getDate("LAST_EDIT_DATE")是null
