我在 SQL Server 2008 中创建了以下存储过程
Create PROCEDURE countInfected @infected int out
AS
Select @infected = COUNT(*) from userInfo where userID NOT IN (Select userID from deletedInfo);
我的java代码如下
CallableStatement infected = con.prepareCall("exec countInfected()");
infected.registerOutParameter(1, java.sql.Types.INTEGER);
infected.execute();
System.out.println("Infected"+ infected.getInt(1));
但它会产生以下错误
core.dtable.Dbase.stored(Dbase.java:51)处的 java.lang.NullPointerException
请指导我哪里错了