org.apache.poi

apache.poi 可用于 word/ppt/excel等文件进行处理

详情见于 -> https://poi.apache.org/components/index.html 导航栏中Component APIs 应用指南

一、Excel (HSSF/XSSF)

public static void creatWorkbook()throws Exception{
        // 创建工作薄
        Workbook wb = new HSSFWorkbook();
        // 创建表
        CreationHelper createHelper = wb.getCreationHelper();
        Sheet sheet = wb.createSheet("new sheet");
        // 创建第一行 ***************************
        Row row = sheet.createRow(0);
        // 创建单元格
        Cell cell = row.createCell(0);
        // 插入单元格数值 （整数、小数、字符串、布尔型）
        cell.setCellValue(1);
        row.createCell(1).setCellValue(1.2);
        row.createCell(2).setCellValue(createHelper.createRichTextString("This is a string"));
        row.createCell(3).setCellValue(true);
        // 创建第二行 * 时间 *************************
        Row row1 = sheet.createRow(1);
        Cell cell1 = row1.createCell(0);
        String localData = LocalDate.now().toString();
        cell1.setCellValue(createHelper.createRichTextString(localData));


        CellStyle cellStyle = wb.createCellStyle();
        cellStyle.setDataFormat(createHelper.createDataFormat().getFormat("m/d/yy h:mm"));
        cell1 = row1.createCell(1);
        cell1.setCellValue(new Date());
        cell1.setCellStyle(cellStyle);

        //you can also set date as java.util.Calendar
        cell1 = row1.createCell(2);
        cell1.setCellValue(Calendar.getInstance());
        cell1.setCellStyle(cellStyle);
        row1.createCell(3).setCellType(CellType.ERROR);

        // 输出文件
        try  (OutputStream fileOut = new FileOutputStream("D:\\资料\\exl\\workbook.xls")) {
            wb.write(fileOut);
        }
    }

读取列宽 -> sheet.getColumnWidth(int index)

public static void main(String [] args) {
        String filePath = "E:/Browers/测试查看默认100列.xls";
        try{
            FileInputStream fs = new FileInputStream(filePath);
            HSSFWorkbook workbook = new HSSFWorkbook(fs);
            HSSFSheet sheet = workbook.getSheetAt(0);
            int lastRowIndex = sheet.getLastRowNum();
            int lastColIndex = getLastColIndex(sheet,lastRowIndex);
            for(int i = 0; i<lastColIndex ;i++){
                System.out.println((sheet.getColumnWidth(i)/512)*100);
            }
        }catch (Exception e){
            System.out.println("错误:" + e.getMessage());
        }
    }

    private static int getLastColIndex(HSSFSheet sheet,int lastRowIndex){
        int currIndex = -1;
        for(int i = 0; i <= lastRowIndex; i++){
            if(sheet.getRow(i) != null){
                if(sheet.getRow(i).getLastCellNum() > currIndex){
                    currIndex = sheet.getRow(i).getLastCellNum();
                }
            }
        }
        return currIndex;
    }