excel工具，利用反射

package util;
 
import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.lang.reflect.Field;
import java.util.ArrayList;
import java.util.List;
 
import jxl.Sheet;
import jxl.Workbook;
import jxl.read.biff.BiffException;
 
/**
 * Excel工具类
 * @author ricky
 * 2016-8-11
 */
public class ExcelOperate {
 
    private Workbook workbook;
    private Sheet currentSheet;
     
    /**
     * 初始化Workbook、Sheet对象，默认选择第一张Sheet
     * @param file
     */
    public ExcelOperate(File file) {
        try {
            workbook = Workbook.getWorkbook(file);