我的代码有两个循环,我的外循环应循环遍历外循环的第一行的内循环的所有行,而对于外循环的第二行,它应循环遍历所有的行内排。
int y1,y2;
float t = 0,s1,s2;
while(rm.next())
{
int currentCol = 0;
cellNumber = new jxl.write.Number (currentCol++, currentRow, index, integerFormat);
index++;
sheet.addCell ( cellNumber );
cellLabel = new Label(currentCol++, currentRow, rs.getString("Name"));
sheet.addCell ( cellLabel );
y1 = rm.getInt("Year");
System.out.println("Year 1: " +y1);
cellNumber = new jxl.write.Number (currentCol++, currentRow, y1 , integerFormat);
sheet.addCell ( cellNumber );
s1 = rm.getFloat("Total_Price");
System.out.println("S1: "+s1);
while (rs.next())
{
y2 = rs.getInt("Year");
System.out.println("Year 2: " +y2);
s2 = rs.getFloat("Total_Price");
System.out.println("S2: " +s2);
if(y1==y2)
{
t = s1+s2;
System.out.println("Toatl Sales:" +t);
cellNumber = new jxl.write.Number (currentCol++, currentRow, t , priceformat);
sheet.addCell ( cellNumber );
}
}
int a = rs.getFetchDirection();
System.out.println("Direction: " +a);
rs.setFetchDirection(ResultSet.FETCH_REVERSE);
cellNumber = new jxl.write.Number (currentCol++, currentRow, s1 , priceformat);
sheet.addCell ( cellNumber );
currentRow++;
}
答案 0 :(得分:9)
使用此:
resultSet.beforeFirst()
来自docs:
抛出: SQLException - 如果发生数据库访问错误;这个方法是 调用闭合的结果集或结果集类型是 TYPE_FORWARD_ONLY
答案 1 :(得分:1)
以下是您要找的内容:
rm.beforeFirst()
将光标移动到此ResultSet对象的前面,就在第一行之前。如果结果集不包含任何行,则此方法无效。
答案 2 :(得分:0)
使用
resultSet.beforeFirst();
但是您必须通过以下方式创建声明:
Statement stmt = connection.createStatement(ResultSet.TYPE_SCROLL_INSENSITIVE, ResultSet.CONCUR_READ_ONLY);
因此它是可遍历的,而不仅仅是一个方向。