java Excel导入、自适应版本、将Excel转成List<map>对象

转载：http://blog.csdn.net/u012662357/article/details/58593020

最近在web开发中遇到excel批量导入，在网上搜了下很少有将excel直接转成java 对象的例子于是自己写了一个。

/**
*  Excel文件流 -->  List <Map<String,Object>>  对象
想直接转成java bean的朋友可以使用fastjson将  List<Map<String,Object>>转成bean对象
*
*/

public class ImportExcelUtil {

    private static Logger log = Logger.getLogger(ImportExcelUtil.class);

    private final static String excel2003L = ".xls"; // 2003- 版本的excel
    private final static String excel2007U = ".xlsx"; // 2007+ 版本的excel

    /**
     * 将流中的Excel数据转成List<Map>
     *
     * @param in
     *            输入流
     * @param fileName
     *            文件名（判断Excel版本）
     * @param mapping
     *            字段名称映射
     * @return
     * @throws Exception
     */
    public static List<Map<String, Object>> parseExcel(InputStream in, String fileName,
            Map<String, String> mapping) throws Exception {
        // 根据文件名来创建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;
        // 返回数据
        List<Map<String, Object>> ls = new ArrayList<Map<String, 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;

            // 取第一行标题
            row = sheet.getRow(0);
            String title[] = null;
            if (row != null) {
                title = new String[row.getLastCellNum()];

                for (int y = row.getFirstCellNum(); y < row.getLastCellNum(); y++) {
                    cell = row.getCell(y);
                    title[y] = (String) getCellValue(cell);
                }

            } else
                continue;
            log.info(JSON.toJSONString(title));

            // 遍历当前sheet中的所有行
            for (int j = 1; j < sheet.getLastRowNum() + 1; j++) {
                row = sheet.getRow(j);
                Map<String, Object> m = new HashMap<String, Object>();
                // 遍历所有的列
                for (int y = row.getFirstCellNum(); y < row.getLastCellNum(); y++) {
                    cell = row.getCell(y);
                    String key = title[y];
                    // log.info(JSON.toJSONString(key));
                    m.put(mapping.get(key), getCellValue(cell));
                }
                ls.add(m);
            }

        }
        work.close();
        return ls;
    }

    /**
     * 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"); // 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;
    }

    public static void main(String[] args) throws Exception {
        File file = new File("D:\\studn.xls");
        FileInputStream fis = new FileInputStream(file);
        Map<String, String> m = new HashMap<String, String>();
        m.put("id", "id");
        m.put("姓名", "name");
        m.put("年龄", "age");
        List<Map<String, Object>> ls = parseExcel(fis, file.getName(), m);
        System.out.println(JSON.toJSONString(ls));
    }
}

输出结果

[{"age":"13","id":"11","name":"张三"},{"age":"23","id":"21","name":"李四"},{"age":"33","id":"31","name":"王五"}]

用到的包
<org.poi-version>3.14</org.poi-version>
    <!-- Excel -->
        <dependency>
            <groupId>org.apache.poi</groupId>
            <artifactId>poi</artifactId>
            <version>${org.poi-version}</version>
        </dependency>
        <dependency>
            <groupId>org.apache.poi</groupId>
            <artifactId>poi-ooxml</artifactId>
            <version>${org.poi-version}</version>
        </dependency>
        <dependency>
            <groupId>org.apache.poi</groupId>
            <artifactId>poi-examples</artifactId>
            <version>${org.poi-version}</version>
        </dependency>
        <dependency>
            <groupId>org.apache.poi</groupId>
            <artifactId>poi-excelant</artifactId>
            <version>${org.poi-version}</version>
        </dependency>

最后返回的数据可以用fastjson直接转成java bean