자바 통계 JXL 엑셀 쓰기

package com.db;
import jxl.Workbook;
import jxl.write.Label;
import jxl.write.WritableSheet;
import jxl.write.WritableWorkbook;
import jxl.write.WriteException;
import jxl.write.biff.RowsExceededException;
import java.io.File;

/**
 * Created by IntelliJ IDEA.
 * User: haoshihai
 * Date: 12-9-19
 * Time:   9:57
 * To change this template use File | Settings | File Templates.
 */
public class JxlExcel {
    WritableWorkbook wwb = null;

    //   content.split(,)
    public void writeExcel(WritableSheet ws, String content, int rowNum) {
        try {
            if (wwb != null && ws != null) {
                putRow(ws, rowNum, content.split(","));
            }
        } catch (Exception e) {
            System.out.println(e.toString());
        }
    }

    //   sheet      
    private void putRow(WritableSheet ws, int rowNum, Object[] cells) throws RowsExceededException, WriteException {
        for (int j = 0; j < cells.length; j++) {//   
            Label cell = new Label(j, rowNum, "" + cells[j]);
            ws.addCell(cell);
        }
    }

    public void startWrite() throws Exception {
        wwb = Workbook.createWorkbook(new File("E:\\test.xls"));
        String title = "ID,userName,pwssword,sex";
        WritableSheet ws = wwb.createSheet("tb_user", 0);
        writeExcel(ws, title, 0);
        wwb.write();
        wwb.close();
    }

    public static void main(String args[]) throws Exception {
        new JxlExcel().startWrite();
    }
}

    jxl.write.Number number = new Number(j, rowNum, Double.valueOf(cells[j].toString()));    
    ws.addCell(number);