写Excel

public class Demo {
    public static void main(String[] args) throws IOException {
        //创建一个excel文件
        HSSFWorkbook workbook = new HSSFWorkbook();

        //创建一个新的sheet工作表
        HSSFSheet sheet = workbook.createSheet("Sheet 1");


        //用于创建超链接
        HSSFCreationHelper creationHelper = workbook.getCreationHelper();
        //创建行和列
        for (int rowIndex = 0; rowIndex < 10; rowIndex++) {
            // 创建行
            HSSFRow row = sheet.createRow(rowIndex);

            //此处设置第一行行高为 510(默认为255)
            if (rowIndex == 0)
                row.setHeight((short) 510); //设置行高

            for (int columnIndex = 0; columnIndex < 10; columnIndex++) {

                //此处设置 第2列 列宽      默认为2048
                if (rowIndex == 0 && columnIndex == 1)
                    sheet.setColumnWidth(columnIndex,4096);
                //创建元素
                HSSFCell cell = row.createCell(columnIndex);

                //为列元素设置字体
                HSSFFont font  = workbook.createFont();
                font.setColor(IndexedColors.RED.getIndex()); // 字体颜色

                HSSFCellStyle cellStyle = workbook.createCellStyle(); // 创建样式
                cellStyle.setFont(font);

                cell.setCellStyle(cellStyle); // 设置样式
                cell.setCellValue("R" + rowIndex + ":C" + columnIndex);
                //添加超链接
                if (rowIndex == 0 && columnIndex == 0){
                    HSSFHyperlink hyperlink = creationHelper.createHyperlink(HyperlinkType.URL);
                    hyperlink.setAddress("https://www.baidu.com");
                    cell.setHyperlink(hyperlink);
                }
            }
        }

        workbook.write(new File("Excel.xls"));
        workbook.close();
    }
}

读Excel

public class Demo {
    public static void main(String[] args) throws IOException {
        Workbook workbook = WorkbookFactory.create(new File("Excel.xls"));
        //获得工作簿数目
        int sheetNum = workbook.getNumberOfSheets();

        //遍历工作簿
        for (int sheetIndex = 0; sheetIndex < sheetNum; sheetIndex++) {
            Sheet sheet = workbook.getSheetAt(sheetIndex);

            int rowNum = sheet.getLastRowNum() + 1;
            //遍历各行
            for (int rowIndex = 0; rowIndex < rowNum; rowIndex++) {
                Row row = sheet.getRow(rowIndex);
                if (row == null)
                    continue;

                int columnNum = row.getPhysicalNumberOfCells();
                //遍历各列的元素
                for (int columnIndex = 0; columnIndex < columnNum; columnIndex++) {
                    //获取超链接地址
                    Cell cell = row.getCell(columnIndex);
                    if (columnIndex == 0 && rowIndex == 0) {
                        System.out.printf("(%s) ", cell.getHyperlink().getAddress());
                    }
                    System.out.printf("%s ", row.getCell(columnIndex).getStringCellValue());
                }
                System.out.println();
            }
        }
        workbook.close();
    }
}