rs.getMetaData().getColumnCount() 的问题

select xx as 矿名,xx1 as 传感器,cast(MAX(a.RTData) as numeric(4,2)) AS 最大值 from book 
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k=rs.getMetaData().getColumnCount();
System.out.println(k);
for(int iii=0;iii<=k;iii++){
Vector tempList = new Vector();
String www=rs.getString(iii);
}
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