Java 使用POI读取导入Excel的工具类

package com.wonhero.utils.util;import org.apache.poi.hssf.usermodel.HSSFCell;import org.apache.poi.ss.usermodel.Cell;import org.apache.poi.ss.usermodel.Row;import org.apache.poi.ss.usermodel.Sheet;import org.apache.poi.ss.usermodel.Workbook;import org.apache.poi.xssf.usermodel.XSSFCell;import org.apache.poi.xssf.usermodel.XSSFWorkbook;import org.springframework.web.multipart.MultipartFile;import java.io.FileInputStream;import java.io.IOException;import java.text.DecimalFormat;import java.util.ArrayList;import java.util.List;/** * Excel导入工具类 * */public class ImportExcelUtils {    /**     * 创建WorkBook对象     *     * @param filePath     * @return     * @throws IOException     */    public static final Workbook createWorkbook(String filePath) throws IOException {        if (filePath.trim().toLowerCase().endsWith("xls")) {            return new XSSFWorkbook(new FileInputStream(filePath));        } else if (filePath.trim().toLowerCase().endsWith("xlsx")) {            return new XSSFWorkbook(new FileInputStream(filePath));        } else {            throw new IllegalArgumentException("不是有效的excel文件格式");        }    }    /**     * 创建WorkBook对象     *     * @param uploadFile     * @return     * @throws IOException     */    public static final Workbook createWorkbook(MultipartFile uploadFile) throws IOException {        return new XSSFWorkbook(uploadFile.getInputStream());    }    /**     * 获取Sheet页面(按名称)     *     * @param wb     * @param sheetName     * @return     */    public static final Sheet getSheet(Workbook wb, String sheetName) {        return wb.getSheet(sheetName);    }    /**     * 获取Sheet页面(按页标)     *     * @param wb     * @param index     * @return     */    public static final Sheet getSheet(Workbook wb, int index) {        return wb.getSheetAt(index);    }    /**     * 获取Sheet页内容     *     * @param sheet     * @return     */    public static final List listFromSheet(Sheet sheet) {        List list = new ArrayList();        for (int r = sheet.getFirstRowNum(); r <= sheet.getLastRowNum(); r++) {            Row row = sheet.getRow(r);            if (row == null || row.getPhysicalNumberOfCells() == 0) continue;            Object[] cells = new Object[row.getLastCellNum()];            for (int c = row.getFirstCellNum(); c <= row.getLastCellNum(); c++) {                Cell cell = row.getCell(c);                if (cell == null) continue;                //判断是否为日期类型                cells[c] = getValueFromCell(cell);            }            list.add(cells);        }        return list;    }    /**     * 获取单元格内信息     *     * @param cell     * @return     */    public static final Object getValueFromCell(Cell cell) {        if (cell == null) {            //System.out.println("Cell is null !!!");            return null;        }        Object result = null;        if (cell instanceof HSSFCell) {            if (cell != null) {                // 单元格类型：Numeric:0,String:1,Formula:2,Blank:3,Boolean:4,Error:5                int cellType = ((HSSFCell) cell).getCellType();                switch (cellType) {                    case HSSFCell.CELL_TYPE_STRING:                        result = ((HSSFCell) cell).getStringCellValue();                        break;                    case HSSFCell.CELL_TYPE_NUMERIC:                        DecimalFormat df = new DecimalFormat("###.####");                        result = df.format(((HSSFCell) cell).getNumericCellValue());                        break;                    case HSSFCell.CELL_TYPE_FORMULA:                        result = ((HSSFCell) cell).getNumericCellValue();                        break;                    case HSSFCell.CELL_TYPE_BOOLEAN:                        result = ((HSSFCell) cell).getBooleanCellValue();                        break;                    case HSSFCell.CELL_TYPE_BLANK:                        result = null;                        break;                    case HSSFCell.CELL_TYPE_ERROR:                        result = null;                        break;                    default:                        System.out.println("枚举了所有类型");                        break;                }            }        } else if (cell instanceof XSSFCell) {            if (cell != null) {                // 单元格类型：Numeric:0,String:1,Formula:2,Blank:3,Boolean:4,Error:5                int cellType = ((XSSFCell) cell).getCellType();                switch (cellType) {                    case XSSFCell.CELL_TYPE_STRING:                        result = ((XSSFCell) cell).getRichStringCellValue().getString();                        break;                    case XSSFCell.CELL_TYPE_NUMERIC:                        DecimalFormat df = new DecimalFormat("###.####");                        result = df.format(((XSSFCell) cell).getNumericCellValue());                        break;                    case XSSFCell.CELL_TYPE_FORMULA:                        result = ((XSSFCell) cell).getNumericCellValue();                        break;                    case XSSFCell.CELL_TYPE_BOOLEAN:                        result = ((XSSFCell) cell).getBooleanCellValue();                        break;                    case XSSFCell.CELL_TYPE_BLANK:                        result = null;                        break;                    case XSSFCell.CELL_TYPE_ERROR:                        result = null;                        break;                    default:                        //System.out.println("枚举了所有类型");                        break;                }            }        }        return result;    }    /**     * 根据Sheet页导入Excel信息     *     * @param filePath   文件路径     * @param sheetIndex Sheet页下标     * @param startRow   开始列 ：默认第一列     * @param startLine  开始行 ：默认第一行     * @throws Exception     */    public static final List importExcelBySheetIndex(String filePath, int sheetIndex            , int startRow, int startLine) throws Exception {        List resultList = null;        //创建WorkBook对象        Workbook wb = createWorkbook(filePath);        // 获取Sheet        Sheet sheet = ImportExcelUtils.getSheet(wb, sheetIndex);        // 判断Sheet是否为空        if (sheet != null) {            // 遍历Sheet            List list = ImportExcelUtils.listFromSheet(sheet);            if (list != null && list.size() > 0) {                resultList = new ArrayList();                if (startLine <= list.size()) {                    for (int i = startLine; i < list.size(); i++) {                        int nullCount = 0;                        Object[] rows = list.get(i);                        if (rows != null && rows.length > 0) {                            List