POI 导入导出工具类

工具类:

package com.jxc.common.utils;
import org.apache.commons.lang3.time.DateFormatUtils;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;
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.ss.util.CellRangeAddress;
import org.apache.poi.xssf.usermodel.*;
import java.beans.IntrospectionException;
import java.beans.PropertyDescriptor;
import java.io.InputStream;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.math.BigDecimal;
import java.text.DecimalFormat;
import java.text.NumberFormat;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Date;
import java.util.List;
import java.util.Map;

public class ExcelUtils {
    private final static String excel2003L =".xls";    //2003- 版本的excel
    private final static String excel2007U =".xlsx";   //2007+ 版本的excel  
    /*************************************文件上传****************************/
    public static  List<List<Object>> getBankListByExcel(InputStream in, String fileName) throws Exception{
        List<List<Object>> list = null;
        //创建Excel工作薄  
        Workbook work = getWorkbook(in,fileName);
        if(null == work){  
            throw new Exception("创建Excel工作薄为空！");  
        }  
        Sheet sheet = null;
        Row row = null;
        Cell cell = null;
          
        list = new ArrayList<List<Object>>();
        //遍历Excel中所有的sheet  
        for (int i = 0; i < work.getNumberOfSheets(); i++) {  
            sheet = work.getSheetAt(i);  
            if(sheet==null){continue;}  
              
            //遍历当前sheet中的所有行  
            for (int j = sheet.getFirstRowNum(); j <= sheet.getLastRowNum(); j++) {
                row = sheet.getRow(j);  
                if(row==null||row.getFirstCellNum()==j){continue;}  
                  
                //遍历所有的列  
                List<Object> li = new ArrayList<Object>();  
                for (int y = row.getFirstCellNum(); y < row.getLastCellNum(); y++) {  
                    cell = row.getCell(y);  
                    li.add(getCellValue(cell));  
                }  
                list.add(li);  
            }  
        }  
//        work.close();  
        return list;  
    }  
      
    /** 
     * 描述：根据文件后缀，自适应上传文件的版本  
     * @param inStr,fileName 
     * @return 
     * @throws Exception 
     */  
    public static  Workbook getWorkbook(InputStream inStr,String fileName) throws Exception{  
        Workbook wb = null;  
        String fileType = fileName.substring(fileName.lastIndexOf("."));  
        if(excel2003L.equals(fileType)){  
            wb = new HSSFWorkbook(inStr);  //2003-
        }else if(excel2007U.equals(fileType)){  
            wb = new XSSFWorkbook(inStr);  //2007+
        }else{  
            throw new Exception("解析的文件格式有误！");  
        }  
        return wb;  
    }  
  
    /** 
     * 描述：对表格中数值进行格式化 
     * @param cell 
     * @return 
     */  
    public static  Object getCellValue(Cell cell){  
        Object value = null;  
        DecimalFormat df = new DecimalFormat("0");  //格式化number String字符
        SimpleDateFormat sdf = new SimpleDateFormat("yyy-MM-dd");  //日期格式化
        DecimalFormat df2 = new DecimalFormat("0.00");  //格式化数字  
          
        switch (cell.getCellType()) {  
        case Cell.CELL_TYPE_STRING:  
            value = cell.getRichStringCellValue().getString();  
            break;  
        case Cell.CELL_TYPE_NUMERIC:  
            if("General".equals(cell.getCellStyle().getDataFormatString())){  
                value = df.format(cell.getNumericCellValue());  
            }else if("m/d/yy".equals(cell.getCellStyle().getDataFormatString())){  
                value = sdf.format(cell.getDateCellValue());  
            }else{  
                value = df2.format(cell.getNumericCellValue());  
            }  
            break;  
        case Cell.CELL_TYPE_BOOLEAN:  
            value = cell.getBooleanCellValue();  
            break;  
        case Cell.CELL_TYPE_BLANK:  
            value = "";  
            break;  
        default:  
            break;  
        }  
        return value;  
    }  
    /****************************************上传结束***************************************
	/**
	     * 多列头创建EXCEL
	     * 
	     * @param sheetName 工作簿名称
	     * @param clazz  数据源model类型
	     * @param objs   excel标题列以及对应model字段名 从数据库查询出来的数据
	     * @param map  标题列行数以及cell字体样式
	     * @return
	     * @throws IllegalArgumentException
	     * @throws IllegalAccessException
	     * @throws InvocationTargetException
	     * @throws ClassNotFoundException
	     * @throws IntrospectionException
	     * @throws ParseException
	     */
	public static XSSFWorkbook createExcelFile(Class clazz, List objs, Map<Integer, List<ExcelBean>> map, String sheetName) throws IllegalArgumentException,IllegalAccessException,
            InvocationTargetException, ClassNotFoundException, IntrospectionException, ParseException {
	        // 创建新的Excel 工作簿
	        XSSFWorkbook workbook = new XSSFWorkbook();
	        // 在Excel工作簿中建一工作表，其名为缺省值, 也可以指定Sheet名称
	        XSSFSheet sheet = workbook.createSheet(sheetName);
	        // 以下为excel的字体样式以及excel的标题与内容的创建，下面会具体分析;
	        createFont(workbook);//字体样式
	        createTableHeader(sheet, map);//创建标题（头）
	        createTableRows(sheet, map, objs, clazz);//创建内容
	        return workbook;
	    }
	private static XSSFCellStyle fontStyle;
	private static XSSFCellStyle fontStyle2;
	public static void createFont(XSSFWorkbook workbook) {
        // 表头
		fontStyle = workbook.createCellStyle();
        XSSFFont font1 = workbook.createFont();
        font1.setBoldweight(XSSFFont.BOLDWEIGHT_BOLD);
        font1.setFontName("黑体");
        font1.setFontHeightInPoints((short) 14);// 设置字体大小
        fontStyle.setFont(font1);
        fontStyle.setBorderBottom(XSSFCellStyle.BORDER_THIN); // 下边框
        fontStyle.setBorderLeft(XSSFCellStyle.BORDER_THIN);// 左边框
        fontStyle.setBorderTop(XSSFCellStyle.BORDER_THIN);// 上边框
        fontStyle.setBorderRight(XSSFCellStyle.BORDER_THIN);// 右边框
        fontStyle.setAlignment(XSSFCellStyle.ALIGN_CENTER); // 居中

        // 内容
        fontStyle2=workbook.createCellStyle();
		XSSFFont font2 = workbook.createFont();
		font2.setFontName("宋体");
		font2.setFontHeightInPoints((short) 10);// 设置字体大小
		fontStyle2.setFont(font2);     
		fontStyle2.setBorderBottom(XSSFCellStyle.BORDER_THIN); // 下边框
        fontStyle2.setBorderLeft(XSSFCellStyle.BORDER_THIN);// 左边框
        fontStyle2.setBorderTop(XSSFCellStyle.BORDER_THIN);// 上边框
        fontStyle2.setBorderRight(XSSFCellStyle.BORDER_THIN);// 右边框
        fontStyle2.setAlignment(XSSFCellStyle.ALIGN_CENTER); // 居中
	}
	
	/**
     * 根据ExcelMapping 生成列头（多行列头）
     * 
     * @param sheet
     *            工作簿
     * @param map
     *            每行每个单元格对应的列头信息
     */
    public static final void createTableHeader(XSSFSheet sheet, Map<Integer, List<ExcelBean>> map) {
        int startIndex=0;//cell起始位置
        int endIndex=0;//cell终止位置

        for (Map.Entry<Integer, List<ExcelBean>> entry : map.entrySet()) {
            XSSFRow row = sheet.createRow(entry.getKey());
            List<ExcelBean> excels = entry.getValue();
            for (int x = 0; x < excels.size(); x++) {
                //合并单元格
                if(excels.get(x).getCols()>1){
                    if(x==0){                                     
                    	endIndex+=excels.get(x).getCols()-1;
                        CellRangeAddress range=new CellRangeAddress(0,0,startIndex,endIndex);
                        sheet.addMergedRegion(range);
                        startIndex+=excels.get(x).getCols();
                    }else{
                        endIndex+=excels.get(x).getCols();
                        CellRangeAddress range=new CellRangeAddress(0,0,startIndex,endIndex);
                        sheet.addMergedRegion(range);
                        startIndex+=excels.get(x).getCols();
                    }
                    XSSFCell cell = row.createCell(startIndex-excels.get(x).getCols());
                    cell.setCellValue(excels.get(x).getHeadTextName());// 设置内容
                    if (excels.get(x).getCellStyle() != null) {
                        cell.setCellStyle(excels.get(x).getCellStyle());// 设置格式
                    }
                    cell.setCellStyle(fontStyle);
                }else{

                    XSSFCell cell = row.createCell(x);
                    cell.setCellValue(excels.get(x).getHeadTextName());// 设置内容
                    if (excels.get(x).getCellStyle() != null) {
                        cell.setCellStyle(excels.get(x).getCellStyle());// 设置格式
                    }
                    cell.setCellStyle(fontStyle);
                }

            }
        }
    }
	
	/**
     * 
     * @param sheet
     * @param map
     * @param objs
     * @param clazz
     */
    @SuppressWarnings("rawtypes")
    public static void createTableRows(XSSFSheet sheet, Map<Integer, List<ExcelBean>> map, List objs, Class clazz)
            throws IllegalArgumentException, IllegalAccessException, InvocationTargetException, IntrospectionException,
            ClassNotFoundException, ParseException {

        int rowindex = map.size();
        int maxKey = 0;
        List<ExcelBean> ems = new ArrayList<ExcelBean>();
        for (Map.Entry<Integer, List<ExcelBean>> entry : map.entrySet()) {
            if (entry.getKey() > maxKey) {
                maxKey = entry.getKey();
            }
        }
        ems = map.get(maxKey);

        List<Integer> widths = new ArrayList<Integer>(ems.size());
        for (Object obj : objs) {
            XSSFRow row = sheet.createRow(rowindex);
            for (int i = 0; i < ems.size(); i++) {
                ExcelBean em = (ExcelBean) ems.get(i);
              // 获得get方法
                PropertyDescriptor pd = new PropertyDescriptor(em.getPropertyName(), clazz);
                Method getMethod = pd.getReadMethod();
                Object rtn = getMethod.invoke(obj);
                String value = "";
                // 如果是日期类型 进行 转换
                if (rtn != null) {
                    if (rtn instanceof Date) {
                        value = DateFormatUtils.format((Date) rtn,"yyyy-MM-dd");
                    } else if(rtn instanceof BigDecimal){
                    	NumberFormat nf = new DecimalFormat("#,##0.00");
                    	value=nf.format((BigDecimal)rtn).toString();
                    } else if((rtn instanceof Integer) && (Integer.valueOf(rtn.toString())<0 )){
                    	value="--";
                    }else {
                        value = rtn.toString();
                    }
                }
                XSSFCell cell = row.createCell(i);
                cell.setCellValue(value);
                cell.setCellType(XSSFCell.CELL_TYPE_STRING);
                cell.setCellStyle(fontStyle2);
                // 获得最大列宽
                int width = value.getBytes().length * 300;
                // 还未设置，设置当前
                if (widths.size() <= i) {
                    widths.add(width);
                    continue;
                }
                // 比原来大，更新数据
                if (width > widths.get(i)) {
                    widths.set(i, width);
                }
            }
            rowindex++;
        }
        // 设置列宽
        for (int index = 0; index < widths.size(); index++) {
            Integer width = widths.get(index);
            width = width < 2500 ? 2500 : width + 300;
            width = width > 10000 ? 10000 + 300 : width + 300;
            sheet.setColumnWidth(index, width);
        }
    }
}

excel对象:

package com.jxc.common.utils;
import lombok.Getter;
import lombok.Setter;
import org.apache.poi.xssf.usermodel.XSSFCellStyle;

/**
 * 
 * @Description: 导入导出excel
 */
@Getter
@Setter
public class ExcelBean implements java.io.Serializable {
    private String headTextName;//列头（标题）名
     private String propertyName;//对应字段名
     private Integer cols;//合并单元格数
     private XSSFCellStyle cellStyle;//2007 excel
     
     public ExcelBean(){

     }
     public ExcelBean(String headTextName, String propertyName){
    	 this.headTextName = headTextName;
         this.propertyName = propertyName;
     }
     public ExcelBean(String headTextName, String propertyName, Integer cols) {
         super();
         this.headTextName = headTextName;
         this.propertyName = propertyName;
         this.cols = cols;
     }

}