依賴:

 <dependency>
            <groupId>org.apache.poi</groupId>
            <artifactId>poi</artifactId>
            <version>3.9</version>
        </dependency>
        <dependency>
            <groupId>org.apache.poi</groupId>
            <artifactId
 
>poi-ooxml</artifactId>
            <version>3.9</version>
        </dependency>

ExcelUtil:

import org.apache.log4j.Logger;
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 org.apache.poi.ss.usermodel.Cell;
import org.apache.poi.ss.usermodel.Workbook;
import org.apache.poi.xssf.usermodel.XSSFCell;
import org.apache.poi.xssf.usermodel.XSSFRow;
import org.apache.poi.xssf.usermodel.XSSFSheet;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;

import
 
 java.io.*;
import java.util.ArrayList;
import java.util.List;

public class ExcelUtil {
    private static final Logger logger = Logger.getLogger(ExcelUtil.class);

    public static List<List<String>> readExcel(File file) throws Exception {
        String fileName = file.getName();
        String[] format = fileName.split("\\.");
        FileInputStream fis = new FileInputStream(file);   //檔案流物件
        logger.info("格式:" + format[1]);
        Workbook wb;
        //根據檔案字尾（xls/xlsx）進行判斷
        if ("xls".equals(format[1])) {
           return readXls(fis);
        } else if ("xlsx".equals(format[1])) {
           return readXlsx(fis);
        }
        return null;
    }

    private static List<List<String>> readXls(InputStream is) throws Exception {
        // HSSFWorkbook 標識整個excel
        HSSFWorkbook hssfWorkbook = new HSSFWorkbook(is);
        List<List<String>> result = new ArrayList<List<String>>();
        int size = hssfWorkbook.getNumberOfSheets();
        // 迴圈每一頁，並處理當前迴圈頁
        for (int numSheet = 0; numSheet < size; numSheet++) {
            // HSSFSheet 標識某一頁
            HSSFSheet hssfSheet = hssfWorkbook.getSheetAt(numSheet);
            if (hssfSheet == null) {
                continue;
            }
            // 處理當前頁，迴圈讀取每一行
            for (int rowNum = 1; rowNum <= hssfSheet.getLastRowNum(); rowNum++) {
                // HSSFRow表示行
                HSSFRow hssfRow = hssfSheet.getRow(rowNum);
                int minColIx = hssfRow.getFirstCellNum();
                int maxColIx = hssfRow.getLastCellNum();
                List<String> rowList = new ArrayList<String>();
                // 遍歷改行，獲取處理每個cell元素
                for (int colIx = minColIx; colIx < maxColIx; colIx++) {
                    // HSSFCell 表示單元格
                    HSSFCell cell = hssfRow.getCell(colIx);
                    if (cell == null) {
                        continue;
                    }
                    rowList.add(getStringVal(cell));
                }
                result.add(rowList);
            }
        }
        return result;
    }

    /**
     * @param @param  path
     * @param @return
     * @param @throws Exception    設定檔案
     * @return List<List   <   String>>    返回型別
     * @throws
     * @Title: readXlsx
     * @Description: 處理Xlsx檔案
     */
    private static List<List<String>> readXlsx(InputStream is) throws Exception {
        XSSFWorkbook xssfWorkbook = new XSSFWorkbook(is);
        List<List<String>> result = new ArrayList<List<String>>();
        // 迴圈每一頁，並處理當前迴圈頁
        for (XSSFSheet xssfSheet : xssfWorkbook) {
            if (xssfSheet == null) {
                continue;
            }
            // 處理當前頁，迴圈讀取每一行
            for (int rowNum = 1; rowNum <= xssfSheet.getLastRowNum(); rowNum++) {
                XSSFRow xssfRow = xssfSheet.getRow(rowNum);
                int minColIx = xssfRow.getFirstCellNum();
                int maxColIx = xssfRow.getLastCellNum();
                List<String> rowList = new ArrayList<String>();
                for (int colIx = minColIx; colIx < maxColIx; colIx++) {
                    XSSFCell cell = xssfRow.getCell(colIx);
                    if (cell == null) {
                        continue;
                    }
                    rowList.add(getStringVal(cell));
                }
                result.add(rowList);
            }
        }
        return result;
    }

    private static String getStringVal(Cell cell) {
        switch (cell.getCellType()) {
            case Cell.CELL_TYPE_BOOLEAN:
                return cell.getBooleanCellValue() ? "TRUE" : "FALSE";
            case Cell.CELL_TYPE_FORMULA:
                return cell.getCellFormula();
            case Cell.CELL_TYPE_NUMERIC:
                cell.setCellType(Cell.CELL_TYPE_STRING);
                return cell.getStringCellValue();
            case Cell.CELL_TYPE_STRING:
                return cell.getStringCellValue();
            default:
                return "";
        }
    }
}