自己写的java excel导出工具类

public class ExcelFactory<T> {
    private static final String EXCEL_FONT_FAMILY_SETTING = "Monaco"; //设置字体
    private static final int EXCEL_FONT_SIZE_SETTING = 12;  //设置字体大小

    private WritableWorkbook writableWorkbook = null;
    private WritableSheet writableSheet = null;

    public WritableWorkbook createExcel(OutputStream os, Excel excel,
                                        List<String> header, List<T> datas, ExcelMapper<T> mapper)
            throws RowsExceededException, WriteException { //生成excel
        try {
            writableWorkbook = Workbook.createWorkbook(os);
            writableSheet = writableWorkbook.createSheet(excel.getSheetName(),
                    excel.getSheetNum());
            SheetSettings settings = writableSheet.getSettings();
            settings.setVerticalFreeze(1);

            // Write the title
            if (header != null && header.size() > 0) {
                for (int i = 0; i < header.size(); i++) {
                    writableSheet.addCell(new Label(i, 0, header.get(i),
                            setHeaderCellStyle(new CellStyle(EXCEL_FONT_FAMILY_SETTING, EXCEL_FONT_SIZE_SETTING))));
                }
            }

            // Write data to file
            if (datas != null && datas.size() > 0) {
                for (int i = 1; i <= datas.size(); i++) {
                    mapper.mapToExcel(writableSheet, datas.get(i - 1),
                            setBodyCellStyle(new CellStyle(EXCEL_FONT_FAMILY_SETTING, EXCEL_FONT_SIZE_SETTING)), i);
                }
            }
        } catch (IOException e) {
            return null;
        }

        return writableWorkbook;
    }

    private WritableCellFormat setHeaderCellStyle(CellStyle style) throws WriteException {
        WritableFont font = new WritableFont(
                WritableFont.createFont(style.getFont()), style.getFontSize(), WritableFont.BOLD);
        WritableCellFormat cellFormat = setCentre(style, font);

        return cellFormat;
    }

    private WritableCellFormat setBodyCellStyle(CellStyle style) throws WriteException {
        WritableFont font = new WritableFont(
                WritableFont.createFont(style.getFont()), style.getFontSize(), WritableFont.NO_BOLD);
        WritableCellFormat cellFormat = setCentre(style, font);

        return cellFormat;
    }

    private WritableCellFormat setCentre(CellStyle style, WritableFont font)
            throws WriteException {
        WritableCellFormat cellFormat = new WritableCellFormat(font);
        cellFormat.setBackground(style.getBgColor());
        cellFormat.setAlignment(Alignment.CENTRE);
        cellFormat.setVerticalAlignment(VerticalAlignment.CENTRE);
        return cellFormat;
    }
}

public class Excel {
    private String sheetName;
    private int sheetNum;

    public Excel() {

    }

    public Excel(String sheetName, int sheetNum) {
        this.sheetName = sheetName;
        this.sheetNum = sheetNum;
    }
    public String getSheetName() {
        return sheetName;
    }
    public void setSheetName(String sheetName) {
        this.sheetName = sheetName;
    }
    public int getSheetNum() {
        return sheetNum;
    }
    public void setSheetNum(int sheetNum) {
        this.sheetNum = sheetNum;
    }
}

public class CellStyle {
    private String font;
    private int fontSize;
    private Colour bgColor = Colour.WHITE;

    public CellStyle() {}

    public CellStyle(String font, int fontSize) {
        this.font = font;
        this.fontSize = fontSize;
    }

    public Colour getBgColor() {
        return bgColor;
    }

    public void setBgColor(Colour bgColor) {
        this.bgColor = bgColor;
    }

    public int getFontSize() {
        return fontSize;
    }

    public void setFontSize(int fontSize) {
        this.fontSize = fontSize;
    }

    public String getFont() {
        return font;
    }

    public void setFont(String font) {
        this.font = font;
    }
}

public interface ExcelMapper<T> {
    void mapToExcel(WritableSheet sheet, T t, WritableCellFormat wcf, int rowNum);
}

public class FinanceExcelMapper implements ExcelMapper<Finance>{
    public void mapToExcel(WritableSheet sheet, Finance finance, WritableCellFormat wcf, int rowNum) {
        try {
            sheet.addCell(new Label(0, rowNum, String.valueOf(finance.getStudentCourseId())));
            sheet.addCell(new Label(1, rowNum, finance.getCardNum()));
            sheet.addCell(new Label(2, rowNum, finance.getStuName()));
            DefaultDictionaryManager manager = DefaultDictionaryManager.getInstance();
            sheet.addCell(new Label(3, rowNum, manager.dictionary(finance.getSignUpComeFrom(), "signUpComeFrom").getItemValue()));
            sheet.addCell(new Label(4, rowNum, finance.getDepartmentName()));
            sheet.addCell(new Label(5, rowNum, finance.getMajorName()));
            sheet.addCell(new Label(6, rowNum, finance.getCourseName()));
            sheet.addCell(new Label(7, rowNum, String.valueOf(finance.getCourseTuition())));
            sheet.addCell(new Label(8, rowNum, manager.dictionary(finance.getCourseDiscount(), "courseDiscount").getItemValue()));
            sheet.addCell(new Label(9, rowNum, String.valueOf(finance.getActualTuition())));
            sheet.addCell(new Label(10, rowNum, finance.getFinanceUser()));
            sheet.addCell(new Label(11, rowNum, finance.getFinanceTime().toString()));


        } catch (RowsExceededException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (WriteException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }
}