利用Java反射机制和poi插件操作excel

最近在公司写一个利用poi插件读取excel的东西，，不想每一个都写一遍解析代码。
就想利用Java的反射机制，写对应的实体类，获取对应excel中的值，下面是解析的代码，仅供参考。
不足之处，望指出
/**
 * 读取Excel的值，对应到T对象上,T属性的顺序对应的Excel的列的顺序
 * 数据默认是有表头的，且读数据时将从表头的下一行开始读取
 * @param sheet sheet表
 * @param clazzRes 生成的VO类，一定要有set，get方法
 * @param <T> Vo类
 * @return Vo集合
 */
public <T> List<T> readSheet(Sheet sheet, T clazzRes){
    if(null == sheet){
        return null;
    }
    Class clazz = clazzRes.getClass();
    List<T> list = new ArrayList<>();
    //获取类属性信息
    Field[]fields = clazz.getDeclaredFields();
    try {
        for (int rowNum = sheet.getFirstRowNum()+1;rowNum<=sheet.getLastRowNum();rowNum++){
            Row row = sheet.getRow(rowNum);
            if (null == row){
                continue;
            }
            T object = (T) clazz.newInstance();
            for(int j = 0; j<fields.length;j++){
                fields[j].setAccessible(true);
                String value = getCellValue(sheet,rowNum,j);
                Method method = null;
                //对应的属性类型
                switch (fields[j].getType().toString()){
                    case "class java.lang.String":
                        method = clazz.getMethod(getSetMethodName(fields[j].getName()), String.class);
                        method.invoke(object,value);
                        break;
                    case "int":
                    case "class java.lang.Integer":
                        method = clazz.getMethod(getSetMethodName(fields[j].getName()), Integer.class);
                        method.invoke(object,Float.valueOf(value).intValue());
                        break;
                    case "long" :
                    case "class java.lang.Long":
                        method = clazz.getMethod(getSetMethodName(fields[j].getName()), Long.class);
                        method.invoke(object,Float.valueOf(value).longValue());
                        break;
                    case "double":
                    case "class java.lang.Double":
                        method = clazz.getMethod(getSetMethodName(fields[j].getName()), Double.class);
                        method.invoke(object,Float.valueOf(value).doubleValue());
                        break;
                    case "short":
                    case "class java.lang.Short":
                        method = clazz.getMethod(getSetMethodName(fields[j].getName()), Short.class);
                        method.invoke(object,Float.valueOf(value).shortValue());
                        break;
                    case "boolean":
                    case "class java.lang.Boolean":
                        method = clazz.getMethod(getSetMethodName(fields[j].getName()), Boolean.class);
                        method.invoke(object,Boolean.valueOf(value));
                        break;
                    case "byte":
                    case "class java.lang.Byte":
                        method = clazz.getMethod(getSetMethodName(fields[j].getName()), Byte.class);
                        method.invoke(object,Float.valueOf(value).byteValue());
                        break;
                    case "class java.util.Date":
                        method = clazz.getMethod(getSetMethodName(fields[j].getName()), Date.class);
                        Date date = getDate(value,format);
                        method.invoke(object,date);
                        break;

                    default:
                        break;
                }
            }
            list.add(object);

        }
    } catch (Exception e) {
        e.printStackTrace();
    }

    return list;
}

/**
 * 创建workbook
 * @param excelType 创建excel的类型，xls或xlsx
 * @return workbook
 */
public Workbook createWorkbook(String excelType){
    Workbook wb;
    if (EXCEL_XLS.equals(excelType)){
        wb = new HSSFWorkbook();
    }else if (EXCEL_XLSX.equals(excelType)){
        wb = new XSSFWorkbook();
    }else {
        return null;
    }
    return wb;
}

/**
 * 创建Excel，Data中包括sheet名称、headers表头，list为数据
 * 表头的顺序一定要和list对象中的顺序一样
 * @param wb workbook
 * @param data sheet数据
 */
public Workbook createSheet(Workbook wb,ExcelData data){
    if(null == wb){
        return null;
    }
    int startCell = 0;
    int startRow = 0;
    if(data.getStartCell()<1){
        startCell = 0;
    }else{
        startCell = data.getStartCell() - 1;
    }

    if(data.getStartRow()<1){
        startRow = 0;
    }else{
        startRow = data.getStartRow() - 1;
    }

    //设置sheet名字
    Sheet sheet = wb.createSheet(data.getSheetName());
    Row row = null;
    row = sheet.createRow(startRow);
    row.setHeightInPoints(20);
    for(int i=0;i<data.getHeaders().length;i++){
        row.createCell(i+startCell,CellType.STRING).setCellValue(data.getHeaders()[i]);
    }

    if(null == data.getList() || data.getList().size() == 0){
        return wb;
    }

    Method method = null;
    Class clazz = data.getList().get(0).getClass();
    Field[] fields = clazz.getDeclaredFields();
    Cell cell;
    Object object;
    try {
        for (int i = 0; i < data.getList().size(); i++) {

            row = sheet.createRow(i+1+startRow);
            for (int j = 0; j < fields.length; j++) {
                fields[j].setAccessible(true);
                method = clazz.getDeclaredMethod(getGetMethodName(fields[j].getName()));
                method.setAccessible(true);
                object = method.invoke(data.getList().get(i));
                switch (fields[j].getType().toString()){
                    case "class java.lang.String":
                        cell = row.createCell(j+startCell,CellType.STRING);
                        cell.setCellValue(object.toString());
                        break;
                    case "int":
                    case "class java.lang.Integer":
                        cell = row.createCell(j+startCell,CellType.NUMERIC);
                        cell.setCellValue((int)object);
                        break;
                    case "double":
                    case "class java.lang.Double":
                        cell = row.createCell(j+startCell,CellType.NUMERIC);
                        cell.setCellValue((double)object);
                        break;
                    case "float":
                    case "class java.lang.Float":
                        cell = row.createCell(j+startCell,CellType.NUMERIC);
                        cell.setCellValue((float)object);
                        break;
                    case "short":
                    case "class java.lang.Short":
                        cell = row.createCell(j+startCell,CellType.NUMERIC);
                        cell.setCellValue((short)object);
                        break;
                    case "byte":
                    case "class java.lang.Byte":
                        cell = row.createCell(j+startCell,CellType.NUMERIC);
                        cell.setCellValue((byte)object);
                        break;
                    case "class java.util.Date":
                        cell = row.createCell(j+startCell,CellType.NUMERIC);
                        cell.setCellValue(getDateStr((Date) object,format));
                        break;
                    case "boolean":
                    case "class java.lang.Boolean":
                        cell = row.createCell(j+startCell,CellType.BOOLEAN);
                        cell.setCellValue((boolean)object);
                        break;
                        default:
                            break;
                }
            }
        }
    }catch (Exception e){
        e.printStackTrace();
    }
    return wb;
}

/**
 * 读取单元格的值
 * @param sheet
 * @param row
 * @param column
 * @return
 */
public String getCellValue(Sheet sheet, int row, int column) {
    String value = null;
    if (isMergedRegion(sheet, row, column)) {
        value = getMergedRegionValue(sheet, row, column);
    } else {
        Row rowData = sheet.getRow(row);
        Cell cell = rowData.getCell(column);
        value = getCellValue(cell);
    }
    return value;
}

/**
 * 获取cell值，将所有的数据转化为String值
 * @param cell
 * @return
 */
private String getCellValue(Cell cell){
    if (null == cell){
        return "";
    }
    if (cell.getCellType() == CellType.STRING) {

        return cell.getStringCellValue();

    } else if (cell.getCellType() == CellType.BOOLEAN) {

        return String.valueOf(cell.getBooleanCellValue());

    } else if (cell.getCellType() == CellType.FORMULA) {

        try {
            return cell.getCellFormula();
        } catch (Exception e) {
            return String.valueOf(cell.getNumericCellValue());
        }

    } else if (cell.getCellType() == CellType.NUMERIC) {

        if(DateUtil.isCellDateFormatted(cell)){
            SimpleDateFormat sdf = new SimpleDateFormat(format);
            return sdf.format(cell.getDateCellValue());
        }
        return String.valueOf(cell.getNumericCellValue());

    } else {
        cell.setCellType(CellType.STRING);
        return cell.getStringCellValue();
    }
}

/**
 * 判断指定的单元格是否是合并单元格
 *
 * @param sheet
 * @param row
 * @param column
 * @return
 */
private boolean isMergedRegion(Sheet sheet, int row, int column) {
    int sheetMergeCount = sheet.getNumMergedRegions();

    for (int i = 0; i < sheetMergeCount; i++) {
        CellRangeAddress ca = sheet.getMergedRegion(i);
        int firstColumn = ca.getFirstColumn();
        int lastColumn = ca.getLastColumn();
        int firstRow = ca.getFirstRow();
        int lastRow = ca.getLastRow();

        if (row >= firstRow && row <= lastRow) {
            if (column >= firstColumn && column <= lastColumn) {

                return true;
            }
        }
    }

    return false;
}

/**
 * 获取合并单元格的值
 * @param sheet
 * @param row
 * @param column
 * @return
 */
private String getMergedRegionValue(Sheet sheet, int row, int column) {
    int sheetMergeCount = sheet.getNumMergedRegions();

    for (int i = 0; i < sheetMergeCount; i++) {
        CellRangeAddress ca = sheet.getMergedRegion(i);
        int firstColumn = ca.getFirstColumn();
        int lastColumn = ca.getLastColumn();
        int firstRow = ca.getFirstRow();
        int lastRow = ca.getLastRow();

        if (row >= firstRow && row <= lastRow) {

            if (column >= firstColumn && column <= lastColumn) {
                Row fRow = sheet.getRow(firstRow);
                Cell fCell = fRow.getCell(firstColumn);
                return getCellValue(fCell);
            }
        }
    }

    return null;
}

/**
 *日期格式化
 * @param dateStr 日期字符串
 * @param format 日期格式
 * @return Date日期
 */
private Date getDate(String dateStr,String format){
    SimpleDateFormat simpleDateFormat = new SimpleDateFormat(format);
    try {
        return simpleDateFormat.parse(dateStr);
    } catch (ParseException e) {
        e.printStackTrace();
    }
    return null;
}

/**
 * 根据Date转str
 * @param date 日期
 * @param format 日期格式
 * @return 日期字符串
 */
private String getDateStr(Date date,String format){
    SimpleDateFormat simpleDateFormat = new SimpleDateFormat(format);
    return simpleDateFormat.format(date);
}

/**
 * 反射属性的set方法名
 * @param fieldStr 属性名字
 * @return 属性对应的set方法
 */
private String getSetMethodName(String fieldStr){
    return "set" + fieldStr.substring(0, 1).toUpperCase() + fieldStr.substring(1);
}

/**
 * 反射属性的get方法名
 * @param fieldStr 属性名字
 * @return 属性对应的get方法
 */
private String getGetMethodName(String fieldStr){
    return "get" + fieldStr.substring(0, 1).toUpperCase() + fieldStr.substring(1);
}


/////////////////////////////////////////////////////这是ＥＸＣＥＬDATE////////////////////////////////

public class ExcelData {

    /**
     * sheet名字
     */
    private String sheetName;
    /**
     * 表头数据
     */
    private String[] headers;
    /**
     * 数据
     */
    private List<?> list;
    /**
     * 开始行
     */
    private Integer startRow;
    /**
     * 开始列
     */
    private Integer startCell;

    public Integer getStartRow() {
        return startRow;
    }

    public void setStartRow(Integer startRow) {
        this.startRow = startRow;
    }

    public Integer getStartCell() {
        return startCell;
    }

    public void setStartCell(Integer startCell) {
        this.startCell = startCell;
    }

    public String getSheetName() {
        return sheetName;
    }

    public void setSheetName(String sheetName) {
        this.sheetName = sheetName;
    }

    public String[] getHeaders() {
        return headers;
    }

    public void setHeaders(String[] headers) {
        this.headers = headers;
    }

    public List<?> getList() {
        return list;
    }

    public void setList(List<?> list) {
        this.list = list;
    }
}