Java 选择何处查询的JDBC问题

Java 选择何处查询的JDBC问题,java,jdbc,Java,Jdbc,我的代码: con = jdbc.connect(); System.out.println("status of con"+con); String query = " select * from BmgCPUTotalUsage where CPUserID='"+CPUserID+"' and MessageTypeID='"+MessageTypeID+"'"; System.out.println(query); PreparedStat

我的代码:

con = jdbc.connect();
        System.out.println("status of con"+con);
String query = " select * from BmgCPUTotalUsage where CPUserID='"+CPUserID+"' and MessageTypeID='"+MessageTypeID+"'";
        System.out.println(query);
        PreparedStatement statement = con.prepareStatement(query);
    ResultSet result = statement.executeQuery();
    System.out.println(result);
    int QuotaUsed=result.getInt("QuotaUsed"); 
输出:

   status of concom.mysql.jdbc.JDBC4Connection@182600f
     select QuotaUsed from BmgCPUTotalUsage where CPUserID='msdp' and MessageTypeID='SMS'
    com.mysql.jdbc.JDBC4ResultSet@16e1dd8
    java.sql.SQLException: Before start of result set.

谁能告诉我如何删除此异常,并从表中获取QuotaUsed。其中QuotaUsed是一个整数。

您确实需要更多地阅读,但简单地说,请尝试以下方法:

ResultSet resultSet = statement.executeQuery();
if (resultSet.next() {
    int quotaUsed = resultSet.getInt("QuotaUsed"); 
}

你有没有经历过接受答案的过程?现在试试看。它创造了奇迹。相信我。