工具类代码：

import lombok.extern.slf4j.Slf4j;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;
import org.apache.poi.ss.usermodel.Cell;
import org.apache.poi.ss.usermodel.Sheet;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;
import org.springframework.web.multipart.MultipartFile;

import java.io.InputStream;
import java.lang.annotation.*;
import java.lang.reflect.Field;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.concurrent.atomic.AtomicInteger;

@Slf4j
public class ReadExcel {
    /**
     * read the Excel file
     *
     * @param file the Excel file
     * @param cls  the Target class
     * @param <T>
     * @return
     */
    public <T> List<T> readExcel(MultipartFile file, Class<T> cls) {
        String postfix = Postfix.getPostfix(file.getOriginalFilename());
        if (CommonPath.OFFICE_EXCEL_2003_POSTFIX.equals(postfix)) {
            return readXls(file, cls);
        } else if (CommonPath.OFFICE_EXCEL_2010_POSTFIX.equals(postfix)) {
            return readXlsx(file, cls);
        }
        return null;
    }

    /**
     * Read the Excel 2003 - 2007
     *
     * @param file the excel file
     * @param cls  the target class
     * @return
     */
    public <T> List<T> readXls(MultipartFile file, Class<T> cls) {
        log.debug("正在读入" + file.getOriginalFilename());
        List<T> dataList = new ArrayList<>();
        HSSFWorkbook workbook = null;
        InputStream is = null;
        try {
            is = file.getInputStream();
            workbook = new HSSFWorkbook(is);
            if (workbook != null) {
                //类映射
                Map<String, List<Field>> classMap = new HashMap<>();
                Field[] fields = cls.getDeclaredFields();
                //获取所有的属性
                for (Field field : fields) {
                    ExcelColumn annotation = field.getAnnotation(ExcelColumn.class);
                    if (annotation != null) {
                        String value = annotation.value();
                        if (!classMap.containsKey(value)) {
                            classMap.put(value, new ArrayList<>());
                        }
                        field.setAccessible(true);
                        classMap.get(value).add(field);
                    }
                }
                Map<Integer, List<Field>> reflectionMap = new HashMap<>();
                Sheet sheet = workbook.getSheetAt(0);
                AtomicInteger ai = new AtomicInteger();
                sheet.forEach(row -> {
                    int i = ai.incrementAndGet();
                    AtomicInteger aj = new AtomicInteger();
                    if (i == 1) {//首行  提取注解
                        row.forEach(cell -> {
                            int j = aj.incrementAndGet();
                            String cellValue = getCellValue(cell);
                            if (classMap.containsKey(cellValue)) {
                                reflectionMap.put(j, classMap.get(cellValue));
                            }
                        });
                    } else {
                        try {
                            T t = cls.newInstance();
                            row.forEach(cell -> {
                                int j = aj.incrementAndGet();

                                if (reflectionMap.containsKey(j)) {
                                    String cellValue = getCellValue(cell);
                                    List<Field> fieldList = reflectionMap.get(j);
                                    for (Field field : fieldList) {
                                        try {
                                            field.set(t, cellValue);
                                        } catch (Exception e) {
                                        //
                                       }
                                    }
                                }
                            });
                            dataList.add(t);
                        }  catch (Exception e) {
                         }
                    }
                });
            }
        } catch (Exception e) {
         } 
          finally {
            if (workbook != null) {
                try {
                    is.close();
                } catch (Exception e) {
                    log.debug("文件流为正确关闭");
                }
            }
        }
        return dataList;
    }

    /**
     * Read the Excel 2010
     *
     * @param file the excel file
     * @param cls  the target class
     * @return
     */
    public <T> List<T> readXlsx(MultipartFile file, Class<T> cls) {
        log.debug("正在读入" + file.getOriginalFilename());
        List<T> dataList = new ArrayList<>();
        XSSFWorkbook workbook = null;
        InputStream is = null;
        try {
            is = file.getInputStream();
            workbook = new XSSFWorkbook(is);
            if (workbook != null) {
                //类映射
                Map<String, List<Field>> classMap = new HashMap<>();
                Field[] fields = cls.getDeclaredFields();
                for (Field field : fields) {
                    ExcelColumn annotation = field.getAnnotation(ExcelColumn.class);
                    if (annotation != null) {
                        String value = annotation.value();
                        if (!classMap.containsKey(value)) {
                            classMap.put(value, new ArrayList<>());
                        }
                        field.setAccessible(true);
                        classMap.get(value).add(field);
                    }
                }
                Map<Integer, List<Field>> reflectionMap = new HashMap<>();
                Sheet sheet = workbook.getSheetAt(0);
                AtomicInteger ai = new AtomicInteger();
                sheet.forEach(row -> {
                    int i = ai.incrementAndGet();
                    AtomicInteger aj = new AtomicInteger();
                    if (i == 1) {//首行  提取注解
                        row.forEach(cell -> {
                            int j = aj.incrementAndGet();
                            String cellValue = getCellValue(cell);
                            if (classMap.containsKey(cellValue)) {
                                reflectionMap.put(j, classMap.get(cellValue));
                            }
                        });
                    } else {
                        try {
                            T t = cls.newInstance();
                            row.forEach(cell -> {
                                int j = aj.incrementAndGet();

                                if (reflectionMap.containsKey(j)) {
                                    String cellValue = getCellValue(cell);
                                    List<Field> fieldList = reflectionMap.get(j);
                                    for (Field field : fieldList) {
                                        try {
                                            field.set(t, cellValue);
                                        } catch (Exception e) {
                                            e.printStackTrace();
                                        }
                                    }
                                }
                            });
                            dataList.add(t);
                        }catch (Exception e) {
                         e.printStackTrace();
                         }
                    }
                });
            }
        } catch (Exception e) {
           e.printStackTrace();
        } finally {
            if (workbook != null) {
                try {
                    is.close();
                } catch (Exception e) {
                }
            }
        }
        return dataList;
    }

    /**
     * 获取excel 单元格数据
     *
     * @param cell
     * @return
     */
    public static String getCellValue(Cell cell) {
        if (cell.getCellType() == cell.CELL_TYPE_BOOLEAN) {
            return String.valueOf(cell.getBooleanCellValue()).trim();
        } else if (cell.getCellType() == cell.CELL_TYPE_NUMERIC) {
            return String.valueOf(cell.getNumericCellValue()).trim();
        } else {
            return String.valueOf(cell.getStringCellValue()).trim();
        }
    }

    /**
     * excel字段对应注解
     */
    @Target({ElementType.FIELD})
    @Retention(RetentionPolicy.RUNTIME)
    @Documented
    public @interface ExcelColumn {
        String value() default "";
    }
}

还有两个类：

public class CommonPath {
    /**
     * 2010版本excel
     */
    public static final String OFFICE_EXCEL_2003_POSTFIX = "xls";
    /**
     * 2003-2007版本excel
     */
    public static final String OFFICE_EXCEL_2010_POSTFIX = "xlsx";
    /**
     * 判断是否为空
     */
    public static final String EMPTY = "";
    /**
     * 以.分隔
     */
    public static final String POINT = ".";
    /**
     * 不是excel文件判断
     */
    public static final String NOT_EXCEL_FILE = " : Not the Excel file!";
    /**
     * 执行中
     */
    public static final String PROCESSING = "Processing...";
}

还有一个：

public class Postfix {
    public static String getPostfix(String path) {
        if (path == null || CommonPath.EMPTY.equals(path.trim())) {
            return CommonPath.EMPTY;
        }
        if (path.contains(CommonPath.POINT)) {
            return path.substring(path.lastIndexOf(CommonPath.POINT) + 1, path.length());
        }
        return CommonPath.EMPTY;
    }
}