为何执行到executeQuery时会死掉?

[baoqingfeng]

public void addTest_subject(Test_subject test_subject)
{
String sqlStr1 =
"insert into Test_subject (service_id,kind_id,subject) values (1,0,'test')";
Connection connect = DBConnectFactory.getInstance().getConnection();
try {
connect.setAutoCommit(false);
PreparedStatement ps = connect.prepareStatement(sqlStr1);
ps.execute();
int id = 0
Statement stmt = connect.createStatement();
ResultSet rs = stmt.executeQuery("select @@IDENTITY as id from test_subject");
if(rs.next()) {
id = rs.getInt(1);
}

connect.commit();
} catch (SQLException e) {
try {
connect.rollback();
} catch (SQLException e1) {
e1.printStackTrace();
}
} finally {
try {
connect.close();
} catch (SQLException e1) {
e1.printStackTrace();
}
}
}

在执行到这句时死掉了,为何呢?
ResultSet rs = stmt.executeQuery("select @@IDENTITY as id from test_subject");

[baoqingfeng]

原来是使用不通连接的问题.谢谢大家