使用Java / Apache POI读取Excel并计算总和

设想：

我正在开发一个将打开excel文件，迭代工作表的行并计算每行数值总计的应用程序。

问题：

考虑以下两种情况：

如果第一种情况的输出是：

A -> 15.0 pages.
B -> 15.0 pages.
T -> 15.0 pages.

为什么在第二种情况下的输出是：

Tanmay -> 15.0 pages.
Abhishek -> 15.0 pages.
Bijoy -> 15.0 pages.

不应该如下吗？

Abhishek -> 15.0 pages.
Bijoy -> 15.0 pages.
Tanmay -> 15.0 pages.

代码：

package miscellaneous;

import org.apache.poi.hssf.usermodel.HSSFCell;
import org.apache.poi.hssf.usermodel.HSSFRow;
import org.apache.poi.hssf.usermodel.HSSFSheet;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;

import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;


/**
 * Created by Sandeep on 8/6/15.
 */
public class TestHarness {

    @SuppressWarnings({ "unchecked" })
    public static void main(String[] args) {
        Map<String, Double> stringDoubleMap = new HashMap<String, Double>();
        stringDoubleMap = readExcelFile();

        for (Map.Entry<String, Double> entry : stringDoubleMap.entrySet()) {
            System.out.println(entry.getKey() + " -> " + entry.getValue() + " pages.");
        }
    }

    @SuppressWarnings("rawtypes")
    private static Map readExcelFile() {

        InputStream fileInputStream = null;
        HSSFWorkbook hssfWorkbook = null;
        HSSFSheet sheet;
        HSSFRow row;
        HSSFCell cell;
        Iterator rowIterator, cellIterator;
        String employeeName=null;
        String sheetName=null;
        double total=0;
        Map<String, Double> empMonthlyProdStat = new HashMap<String, Double>();

       try {
           fileInputStream = new FileInputStream("D:\\Sandeep\\TestExcelWorkbook.xls");
           hssfWorkbook = new HSSFWorkbook(fileInputStream);
           sheet = hssfWorkbook.getSheetAt(0);
           sheetName = sheet.getSheetName();
           rowIterator = sheet.rowIterator();

           while (rowIterator.hasNext()) {
               row = (HSSFRow) rowIterator.next();
               cellIterator = row.cellIterator();
               while (cellIterator.hasNext()) {
                   cell = (HSSFCell) cellIterator.next();

                   if (cell.getCellType() == HSSFCell.CELL_TYPE_STRING) {
                       employeeName = cell.getStringCellValue();
                   } else if (cell.getCellType() == HSSFCell.CELL_TYPE_NUMERIC) {
                       total = total + cell.getNumericCellValue();
                   } else {// Handle Boolean, Formula, Errors
                   }
               }
               empMonthlyProdStat.put(employeeName, total);
               total = 0;
           }
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            try {
                hssfWorkbook.close();
                fileInputStream.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
        System.out.println(sheetName + "\n" + "------------");
        return empMonthlyProdStat;
    }

}