java - Hibernate 查询将 count 转换为 int？

Question

我收到此错误:

java.lang.ClassCastException: java.math.BigInteger cannot be cast to java.lang.Integer

我的想法是检查选择的计数值，但我在转换它时遇到问题。

附上下面的代码。

有什么想法吗？

public List<Map<String, Object>> contaQuery(String sqlCount) throws MensagemException {

    Session session = HibernateUtil.getSession();
    try {

        String sql = sqlCount;
        int query = ((Integer) session.createSQLQuery("select count(*) from (" + sqlCount + ") as subquery")
                .uniqueResult());

        if (query <= 50000) {

            return rodarQuery(sql);
        } else {

            throw new MensagemException("Too many Registers");

        }

    } finally {
        session.close();

    }

}

Answer 1

正如 Farlan 评论中所述， 通过调用 intValue()

将 BigInteger 返回值从 uniqueResult 转换为 Integer

final Query query;
final BigInteger bigResult;
final int result;

query = session.createSQLQuery("select count(*) from (" + sqlCount + ") as subquery");
bigResult = (BigInteger)query.uniqueResult();

if (bigResult != null)
{
    result = bigResult.intValue();
}
else
{
    result = ...some value of your choosing, perhaps 0.
)

if (result < 50000)
... stuff