poi-excel-添加水印
1、官网快速指南
https://poi.apache.org/components/spreadsheet/quick-guide.html
访问如上地址可以查看到poi的相关操作方式:
- How to create a new workbook
- How to create a sheet
- How to create cells
- How to create date cells
- Working with different types of cells
- Iterate over rows and cells
- Getting the cell contents
- Text Extraction
- Files vs InputStreams
- Aligning cells
- Working with borders
- Fills and color
- Merging cells
- Working with fonts
- ......
https://archive.apache.org/dist/poi/release/src/
https://archive.apache.org/dist/poi/release/bin/
2、如何处理水印
在excel中没有水印的概念,只能通过其他形式视觉上达到水印的效果;
方式一:可以通过页眉页脚的方式:
优点:全文覆盖、打印预览可查看 缺点:无法编辑、在非打印预览视图下无法查看
方式二:插入图片方式
优点:在非打印预览视图下可以查看 缺点:打印的时候无法展示
3、实现方式
3.1、页眉页脚实现方式
3.1.1 pom依赖
<!-- Apache POI 核心库 -->
<dependency><groupId>org.apache.poi</groupId><artifactId>poi-ooxml</artifactId><version>5.2.3</version>
</dependency><!-- OOXML 模式库(提供 CTLocking 等类) -->
<dependency><groupId>org.apache.poi</groupId><artifactId>poi-ooxml-lite</artifactId><version>5.2.3</version>
</dependency>
3.1.2 简单代码
public static void buildHeaderAndFooter () throws IOException {// 创建文档Workbook wb = new HSSFWorkbook();// 创建sheet页Sheet sheet = wb.createSheet("sheet名称");// 创建行Row row = sheet.createRow(0);// 创建列Cell cell = row.createCell(0);// 设置单元格内容cell.setCellValue("测试测试");// 获取页眉Header header = sheet.getHeader();// 设置页眉header.setCenter("&\"微软雅黑,Bold\"&14&KAAAAAA 公司机密 - 严禁外传 - 页眉");sheet.setMargin(Sheet.HeaderMargin, 0.8);// 获取页脚Footer footer = sheet.getFooter();// 设置页脚footer.setCenter("&\"微软雅黑,Bold\"&14&KAAAAAA 公司机密 - 严禁外传 - 页脚");sheet.setMargin(Sheet.FooterMargin, 0.8);// TODO 需要根据自己的本地地址修改try (OutputStream fileOut = new FileOutputStream("D://workbook.xls")) {wb.write(fileOut);}}
3.1.3 效果
普通视图下: 没有任何效果
预览模式下:页眉页脚展示咱们得水印
3.2 背景图片实现方式
3.2.1 pom依赖
<!-- Apache POI 核心库 -->
<dependency><groupId>org.apache.poi</groupId><artifactId>poi-ooxml</artifactId><version>5.2.3</version>
</dependency><!-- OOXML 模式库(提供 CTLocking 等类) -->
<dependency><groupId>org.apache.poi</groupId><artifactId>poi-ooxml-lite</artifactId><version>5.2.3</version>
</dependency>
3.2.2 简单代码
public static void picture() throws IOException{// 创建文档Workbook wb = new XSSFWorkbook();// 背景图片的位置 TODO 需要修改成本地地址InputStream is = new FileInputStream("D://a.png");byte[] bytes = IOUtils.toByteArray(is);// 设置成背景图片int pictureIdx = wb.addPicture(bytes, Workbook.PICTURE_TYPE_JPEG);is.close();CreationHelper helper = wb.getCreationHelper();// 创建sheet页Sheet sheet = wb.createSheet();// 创建绘图容器(drawing patriarch)这是 Excel 中所有形状(包括图片)的顶级容器。每个 sheet 只能有一个绘图容器。Drawing drawing = sheet.createDrawingPatriarch();// 创建锚点(ClientAnchor)对象。锚点用于确定图片在 sheet 中的位置和大小ClientAnchor anchor = helper.createClientAnchor();// 设置起始列(从0开始计数)anchor.setCol1(3);// 设置起始行(从0开始计数)anchor.setRow1(2);Picture pict = drawing.createPicture(anchor, pictureIdx);// 根据图片原始尺寸自动调整显示大小pict.resize();// 保存excel文件地址,TODO 需根据本地地址调整String file = "D://picture.xls";if (wb instanceof XSSFWorkbook) file += "x";try (OutputStream fileOut = new FileOutputStream(file)) {wb.write(fileOut);}}
3.2.3 效果
不足之处在于添加的背景图片可以被删除,这样水印就没啥意义了
3.2.4 针对水印可被删除的改进方式
代码调整
public static void buildPicture() throws IOException{// 创建文档XSSFWorkbook wb = new XSSFWorkbook(); //or new HSSFWorkbook();// 背景图片的位置 TODO 需要修改成本地地址InputStream is = new FileInputStream("D://a.png");byte[] bytes = IOUtils.toByteArray(is);// 添加图片到工作簿int pictureIdx = wb.addPicture(bytes, Workbook.PICTURE_TYPE_JPEG);// 返回工作簿中所有图片的列表POIXMLDocumentPart poixmlDocumentPart = wb.getAllPictures().get(pictureIdx);CreationHelper helper = wb.getCreationHelper();// 创建sheet页XSSFSheet sheet = wb.createSheet();/*** getPackagePart() 获取图片在 OOXML 包中的物理表示(即 ZIP 包中的一个文件)。* getPartName() 返回该文件的路径(如 /xl/media/image1.png)。*/PackagePartName ppn = poixmlDocumentPart.getPackagePart().getPartName();String relType = XSSFRelation.IMAGES.getRelation();PackageRelationship pr = sheet.getPackagePart().addRelationship(ppn, TargetMode.INTERNAL, relType, null);// 设置图片为工作表背景sheet.getCTWorksheet().addNewPicture().setId(pr.getId());String file = "D://picture.xls";if (wb instanceof XSSFWorkbook) file += "x";try (OutputStream fileOut = new FileOutputStream(file)) {wb.write(fileOut);}is.close();}
效果如下: 水印无法选中也无法删除
4、完整示例
主要是使用背景图片的方式来实现excel的水印效果
4.1、pom依赖
<!-- Apache POI 核心库 -->
<dependency><groupId>org.apache.poi</groupId><artifactId>poi-ooxml</artifactId><version>5.2.3</version>
</dependency><!-- OOXML 模式库(提供 CTLocking 等类) -->
<dependency><groupId>org.apache.poi</groupId><artifactId>poi-ooxml-lite</artifactId><version>5.2.3</version>
</dependency>
4.2、代码
package water1;import org.apache.poi.ooxml.POIXMLDocumentPart;
import org.apache.poi.openxml4j.opc.PackagePartName;
import org.apache.poi.openxml4j.opc.PackageRelationship;
import org.apache.poi.openxml4j.opc.TargetMode;
import org.apache.poi.ss.usermodel.*;
import org.apache.poi.ss.util.CellRangeAddress;
import org.apache.poi.xssf.usermodel.XSSFRelation;
import org.apache.poi.xssf.usermodel.XSSFSheet;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;import javax.imageio.ImageIO;
import java.awt.Color;
import java.awt.Font;
import java.awt.*;
import java.awt.geom.AffineTransform;
import java.awt.image.BufferedImage;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.text.SimpleDateFormat;
import java.util.Date;public class ExcelWatermarkGenerator {public static void main(String[] args) {try {String outputFile = "D://平铺水印数据表.xlsx";createTiledWatermarkExcel(outputFile);System.out.println("成功创建带平铺水印的Excel文件: " + new File(outputFile).getAbsolutePath());} catch (Exception e) {System.err.println("创建Excel文件时出错: " + e.getMessage());e.printStackTrace();}}public static void createTiledWatermarkExcel(String outputPath) throws Exception {// 1. 创建工作簿XSSFWorkbook workbook = new XSSFWorkbook();XSSFSheet sheet = (XSSFSheet)workbook.createSheet("销售数据");// 2. 添加标题行addTitleRow(sheet);// 3. 添加示例数据addSampleData(sheet);// 4. 设置列宽setColumnWidths(sheet);// 5. 创建平铺水印图片 TODO “公司机密” 可替换成需要的水印文字byte[] watermarkImage = createTiledWatermarkImage("公司机密", 4, 3); // 4列3行平铺// 6. 添加水印到ExceladdWatermarkToSheet(workbook, sheet, watermarkImage);// 7. 添加WPS兼容的页眉文本水印addHeaderWatermarkForWPS(sheet);// 8. 设置打印选项setupPrintSettings(sheet);// 9. 保存文件try (FileOutputStream out = new FileOutputStream(outputPath)) {workbook.write(out);}workbook.close();}private static void addTitleRow(Sheet sheet) {Row titleRow = sheet.createRow(0);titleRow.setHeightInPoints(25);CellStyle titleStyle = createTitleStyle(sheet.getWorkbook());String[] titles = {"产品名称", "生产日期", "库存数量", "单价(元)", "总价值"};for (int i = 0; i < titles.length; i++) {Cell cell = titleRow.createCell(i);cell.setCellValue(titles[i]);cell.setCellStyle(titleStyle);}}private static CellStyle createTitleStyle(Workbook workbook) {CellStyle style = workbook.createCellStyle();style.setFillForegroundColor(IndexedColors.ROYAL_BLUE.getIndex());style.setFillPattern(FillPatternType.SOLID_FOREGROUND);org.apache.poi.ss.usermodel.Font font = workbook.createFont();font.setBold(true);font.setFontHeightInPoints((short) 12);font.setColor(IndexedColors.WHITE.getIndex());style.setFont(font);style.setBorderTop(BorderStyle.THIN);style.setBorderBottom(BorderStyle.THIN);style.setBorderLeft(BorderStyle.THIN);style.setBorderRight(BorderStyle.THIN);style.setTopBorderColor(IndexedColors.BLUE.getIndex());style.setAlignment(HorizontalAlignment.CENTER);style.setVerticalAlignment(VerticalAlignment.CENTER);return style;}private static void addSampleData(Sheet sheet) {CellStyle dateStyle = createDateStyle(sheet.getWorkbook());CellStyle currencyStyle = createCurrencyStyle(sheet.getWorkbook());String[] products = {"智能手机", "笔记本电脑", "平板电脑", "智能手表", "蓝牙耳机"};SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");for (int i = 1; i <= 30; i++) {Row row = sheet.createRow(i);// 产品名称row.createCell(0).setCellValue(products[i % products.length] + " " + (i % 5 + 1) + "代");// 生产日期Cell dateCell = row.createCell(1);Date date = new Date(System.currentTimeMillis() - (i * 24 * 60 * 60 * 1000L));dateCell.setCellValue(date);dateCell.setCellStyle(dateStyle);// 库存数量row.createCell(2).setCellValue(100 + (int)(Math.random() * 500));// 单价Cell priceCell = row.createCell(3);double price = 500 + (Math.random() * 3000);priceCell.setCellValue(price);priceCell.setCellStyle(currencyStyle);// 总价值(公式计算)Cell valueCell = row.createCell(4);valueCell.setCellFormula("C" + (i+1) + "*D" + (i+1));valueCell.setCellStyle(currencyStyle);}}private static CellStyle createDateStyle(Workbook workbook) {CellStyle style = workbook.createCellStyle();style.setLocked(false); // 允许编辑CreationHelper createHelper = workbook.getCreationHelper();style.setDataFormat(createHelper.createDataFormat().getFormat("yyyy-mm-dd"));return style;}private static CellStyle createCurrencyStyle(Workbook workbook) {CellStyle style = workbook.createCellStyle();style.setLocked(false); // 允许编辑style.setDataFormat((short) BuiltinFormats.getBuiltinFormat("¥#,##0.00"));return style;}private static void setColumnWidths(Sheet sheet) {sheet.setColumnWidth(0, 25 * 256); // 产品名称sheet.setColumnWidth(1, 15 * 256); // 生产日期sheet.setColumnWidth(2, 12 * 256); // 库存数量sheet.setColumnWidth(3, 12 * 256); // 单价sheet.setColumnWidth(4, 15 * 256); // 总价值}private static byte[] createTiledWatermarkImage(String text, int cols, int rows) throws IOException {// 1. 设置单个水印单元尺寸int cellWidth = 300;int cellHeight = 200;// 2. 计算总图片尺寸int totalWidth = cellWidth * cols;int totalHeight = cellHeight * rows;// 3. 创建透明背景图片BufferedImage image = new BufferedImage(totalWidth, totalHeight, BufferedImage.TYPE_INT_ARGB);Graphics2D g2d = image.createGraphics();// 4. 设置透明背景g2d.setComposite(AlphaComposite.Clear);g2d.fillRect(0, 0, totalWidth, totalHeight);g2d.setComposite(AlphaComposite.Src);// 5. 设置水印样式g2d.setRenderingHint(RenderingHints.KEY_TEXT_ANTIALIASING, RenderingHints.VALUE_TEXT_ANTIALIAS_ON);g2d.setColor(new Color(180, 180, 180, 50)); // 半透明灰色// 6. 使用WPS兼容字体Font font = new Font("微软雅黑", Font.BOLD, 36);g2d.setFont(font);// 7. 在网格中平铺水印for (int row = 0; row < rows; row++) {for (int col = 0; col < cols; col++) {// 计算当前单元中心位置int centerX = col * cellWidth + cellWidth / 2;int centerY = row * cellHeight + cellHeight / 2;// 保存当前变换AffineTransform originalTransform = g2d.getTransform();// 移动到当前单元中心g2d.translate(centerX, centerY);// 旋转文本g2d.rotate(Math.toRadians(-30));// 计算文本位置(居中)FontMetrics metrics = g2d.getFontMetrics();int textWidth = metrics.stringWidth(text);int x = -textWidth / 2;int y = metrics.getHeight() / 4;// 绘制水印文本g2d.drawString(text, x, y);// 恢复原始变换g2d.setTransform(originalTransform);}}g2d.dispose();// 8. 将图片转换为字节数组ByteArrayOutputStream baos = new ByteArrayOutputStream();ImageIO.write(image, "PNG", baos);return baos.toByteArray();}private static void addWatermarkToSheet(XSSFWorkbook workbook, XSSFSheet sheet, byte[] watermarkImage) throws Exception {// 1. 添加图片到工作簿int pictureIdx = workbook.addPicture(watermarkImage, Workbook.PICTURE_TYPE_PNG);// 返回工作簿中所有图片的列表POIXMLDocumentPart poixmlDocumentPart = workbook.getAllPictures().get(pictureIdx);CreationHelper helper = workbook.getCreationHelper();/*** getPackagePart() 获取图片在 OOXML 包中的物理表示(即 ZIP 包中的一个文件)。* getPartName() 返回该文件的路径(如 /xl/media/image1.png)。*/PackagePartName ppn = poixmlDocumentPart.getPackagePart().getPartName();String relType = XSSFRelation.IMAGES.getRelation();PackageRelationship pr = sheet.getPackagePart().addRelationship(ppn, TargetMode.INTERNAL, relType, null);// 设置图片为工作表背景sheet.getCTWorksheet().addNewPicture().setId(pr.getId());}private static void addHeaderWatermarkForWPS(Sheet sheet) {// WPS兼容性:添加文本水印到页眉Header header = sheet.getHeader();header.setCenter("&\"微软雅黑,Bold\"&14&KAAAAAA 公司机密 - 严禁外传");sheet.setMargin(Sheet.HeaderMargin, 0.8);}private static void setupPrintSettings(Sheet sheet) {// 1. 设置页面为横向sheet.getPrintSetup().setLandscape(true);// 2. 设置页边距sheet.setMargin(Sheet.TopMargin, 0.7);sheet.setMargin(Sheet.BottomMargin, 0.7);sheet.setMargin(Sheet.LeftMargin, 0.5);sheet.setMargin(Sheet.RightMargin, 0.5);// 3. 设置打印标题行sheet.setRepeatingRows(CellRangeAddress.valueOf("1:1"));// 4. 设置网格线sheet.setDisplayGridlines(true);sheet.setPrintGridlines(true);// 5. 设置缩放比例sheet.setZoom(90); // 90%缩放}
}