java 将 bigint 转换为 long
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Cast bigint to long
提问by Muhammad Imran Tariq
I am getting data from a database. I am getting classcastexception. In database my id is saved as BIGINT but in code(object) it is long. Is there is any problem while casting bigint to long?
我正在从数据库中获取数据。我正在收到 classcastexception。在数据库中，我的 id 被保存为 BIGINT 但在代码（对象）中它很长。将 bigint 转换为 long 时是否有任何问题？
采纳答案by aioobe
If this is MySql, you should probably use java.math.BigDecimal.
如果这是 MySql，您可能应该使用java.math.BigDecimal.
See the table at Java, JDBC and MySQL Types.
请参阅Java、JDBC 和 MySQL 类型中的表格。
回答by Lucas de Oliveira
have you tried casting your value to BigInteger first and then get the long value with longValue()? It should work. And aioobe is right, check for null values also.
您是否尝试先将您的值转换为 BigInteger，然后使用 longValue() 获取长值？它应该工作。aioobe 是对的，还要检查空值。
cheers!
干杯！
回答by Muhammad Waqas Dilawar
I was getting error java.math.BigInteger cannot be cast to java.lang.Longbecause I was getting the BigIntegerwhile querying using Spring Data native query, so then I've resolved using below code.
我收到错误java.math.BigInteger cannot be cast to java.lang.Long是因为我在使用 Spring Data 本机查询进行查询时得到了BigInteger，所以我使用下面的代码解决了这个问题。
((BigInteger)nativeQuery.getSingleResult()).longValue()
