Java把列表数据导出为PDF文件，同时加上PDF水印

一、实现效果

二、遇到的问题

1. 实现导出PDF主体代码参考：Java纯代码实现导出PDF功能，下图是原作者实现的效果
   
2. 导出报错Font 'STSong-Light' with 'UniGB-UCS2-H' is not recognized.。参考：itext 生成 PDF(五) 使用外部字体

网上都是说jar包的版本不对，导致的字体兼容性问题。换了jar包版本发现没效果，后来索性直接把字体下载到本地直接引入。

3. jar包发布到服务器上导出PDF的时候发生报错BOOT-INF/classes!/fonts/SimSun.ttf not exists。

可以看到字体文件在jar目录下面是有的，但是发现classes后面多了个叹号。这是引入外部字体方式不对，后改用问题2参考文章的第三种写法就没问题了。

4. 添加水印参考：itextpdf5.5.13给pdf添加图片水印、添加文字水印（平铺）、添加文字水印（单个）、添加页眉、页脚、页眉事件、添加图片

三、测试数据展示

list：子节点数据
0 = {BasBudgetDetailVo@16046} "BasBudgetDetailVo(budgetId=2064535550, functionId=231231232, budgetQuantity=3, totalPrice=2664.00, functionName=功能1, functionDescription=功能1描述, functionUnit=套, functionPrice=888.00, parentId=231234512, functionSort=1)"
1 = {BasBudgetDetailVo@16047} "BasBudgetDetailVo(budgetId=2039369726, functionId=231236478, budgetQuantity=1, totalPrice=888.00, functionName=功能1, functionDescription=功能1描述, functionUnit=套, functionPrice=888.00, parentId=231234879, functionSort=1)"
2 = {BasBudgetDetailVo@16048} "BasBudgetDetailVo(budgetId=2039369725, functionId=231236473, budgetQuantity=1, totalPrice=888.00, functionName=功能2, functionDescription=功能2描述, functionUnit=套, functionPrice=888.00, parentId=231234879, functionSort=2)"
3 = {BasBudgetDetailVo@16049} "BasBudgetDetailVo(budgetId=2056146943, functionId=231231241, budgetQuantity=1, totalPrice=888.00, functionName=功能2, functionDescription=功能2描述, functionUnit=套, functionPrice=888.00, parentId=231234512, functionSort=2)"
4 = {BasBudgetDetailVo@16050} "BasBudgetDetailVo(budgetId=2047758334, functionId=231236487, budgetQuantity=1, totalPrice=888.00, functionName=功能3, functionDescription=功能3描述, functionUnit=套, functionPrice=888.00, parentId=231234512, functionSort=3)"
5 = {BasBudgetDetailVo@16051} "BasBudgetDetailVo(budgetId=2039369724, functionId=231231245, budgetQuantity=1, totalPrice=888.00, functionName=功能3, functionDescription=功能3描述, functionUnit=套, functionPrice=888.00, parentId=231234879, functionSort=3)"
6 = {BasBudgetDetailVo@16052} "BasBudgetDetailVo(budgetId=2047758333, functionId=231231597, budgetQuantity=1, totalPrice=888.00, functionName=功能4, functionDescription=功能4描述, functionUnit=套, functionPrice=888.00, parentId=231234512, functionSort=4)"
7 = {BasBudgetDetailVo@16053} "BasBudgetDetailVo(budgetId=2030981118, functionId=231233154, budgetQuantity=1, totalPrice=888.00, functionName=功能4, functionDescription=功能4描述, functionUnit=套, functionPrice=888.00, parentId=231234879, functionSort=4)"
8 = {BasBudgetDetailVo@16054} "BasBudgetDetailVo(budgetId=2030981117, functionId=231234596, budgetQuantity=1, totalPrice=888.00, functionName=功能5, functionDescription=功能5描述, functionUnit=套, functionPrice=888.00, parentId=231234879, functionSort=5)"
9 = {BasBudgetDetailVo@16055} "BasBudgetDetailVo(budgetId=2030981116, functionId=231235487, budgetQuantity=1, totalPrice=888.00, functionName=功能6, functionDescription=功能6描述, functionUnit=套, functionPrice=888.00, parentId=231234879, functionSort=6)"

functionInfoList：根节点数据
0 = {BasFunctionInfo@16090} "BasFunctionInfo(functionId=231234512, functionName=模块1, functionDescription=, functionUnit=0, functionPrice=0.00, createName=管理员, createBy=admin, createTime=Wed Jan 24 16:56:35 CST 2024, updateName=管理员, updateBy=admin, updateTime=Wed Jan 24 16:56:38 CST 2024, functionQuantity=null, functionSort=1, parentId=null)"
1 = {BasFunctionInfo@16091} "BasFunctionInfo(functionId=231234879, functionName=模块2, functionDescription=, functionUnit=0, functionPrice=0.00, createName=管理员, createBy=admin, createTime=Wed Jan 24 16:56:35 CST 2024, updateName=管理员, updateBy=admin, updateTime=Wed Jan 24 16:56:38 CST 2024, functionQuantity=null, functionSort=2, parentId=null)"

matchList：当前节点的子节点数据

四、jar包引入

<!--导出pdf所需包-->
<dependency>
	<groupId>com.itextpdf</groupId>
	<artifactId>itextpdf</artifactId>
	<version>5.5.10</version>
</dependency>
<dependency>
	<groupId>com.itextpdf</groupId>
	<artifactId>itext-asian</artifactId>
	<version>5.2.0</version>
</dependency>
</dependencies>

五、外部字体引入

字体文件资源自己百度，直接搜SimSun.ttf字体下载不难找

六、代码实现

private final ResourceLoader resourceLoader;

public BasBudgetDetailServiceImpl(ResourceLoader resourceLoader) {
    this.resourceLoader = resourceLoader;
}

/**
 * 导出pdf
 * 
 * @param response
 * @throws Exception
 */
@Override
public void downloadPdf(HttpServletResponse response) throws Exception {
	// 业务数据，根据需求查询获取
    // 子节点数据
    List<BasBudgetDetailVo> list;
    // 根子节点数据
    List<BasFunctionInfo> functionInfoList;

    // 定义全局的字体静态变量
    Font content = null;
    Resource resource = resourceLoader.getResource("classpath:/fonts/SimSun.ttf");
    InputStream inputStream = resource.getInputStream();
    BaseFont bfChinese = null;
    try {
        // 字体
        bfChinese = BaseFont.createFont("SimSun.ttf", BaseFont.IDENTITY_H, BaseFont.EMBEDDED, true, IOUtils.toByteArray(inputStream), null);
        content = new Font(bfChinese, 10, Font.NORMAL);
    } catch (Exception e) {
        e.printStackTrace();
    }
    BaseFont bf = null;
    Font font = null;
    try {
        //创建字体
        bf = BaseFont.createFont("SimSun.ttf", BaseFont.IDENTITY_H, BaseFont.EMBEDDED, true, IOUtils.toByteArray(inputStream), null);
        //使用字体并给出颜色
        font = new Font(bf, 20, Font.BOLD, BaseColor.BLACK);
    } catch (Exception e) {
        e.printStackTrace();
    }
    Document document = new Document(new RectangleReadOnly(842F, 595F));
    try {
        PdfWriter pdfWriter = PdfWriter.getInstance(document, response.getOutputStream());
        //打开生成的pdf文件
        document.open();
        //设置标题
        Paragraph paragraph = new Paragraph("这是标题文档标题", font);
        paragraph.setAlignment(1);
        //引用字体
        document.add(paragraph);

        // 总额
        BigDecimal detailTotal = BigDecimal.valueOf(0);
        for (BasFunctionInfo functionInfo : functionInfoList) {
            // 匹配明细
            List<BasBudgetDetailVo> matchList = list.stream().filter(item ->
                            String.valueOf(item.getParentId()).equals(String.valueOf(functionInfo.getFunctionId())))
                    .collect(Collectors.toList());

            // 设置表格的列宽和列数
            float[] widths = {10f, 35f, 70f, 10f, 10f, 20f, 20f};
            PdfPTable table = new PdfPTable(widths);
            table.setSpacingBefore(20f);
            // 设置表格宽度为100%
            table.setWidthPercentage(100.0F);
            table.setHeaderRows(1);
            table.getDefaultCell().setHorizontalAlignment(1);
            //列表-表头
            String[] titleList = new String[]{"序号", "功能名称", "功能描述", "数量", "单位", "单价（元）", "总价（元）"};
            addTableTitle(table, content, titleList);
            // 模块总额
            BigDecimal modelTotal = BigDecimal.valueOf(0);
            //列表数据
            if (matchList.size() > 0) {
                Integer index = 1;
                for (BasBudgetDetailVo item : matchList) {
                    PdfPCell cell1 = new PdfPCell(new Paragraph(String.valueOf(index), content));
                    PdfPCell cell2 = new PdfPCell(new Paragraph(item.getFunctionName(), content));
                    PdfPCell cell3 = new PdfPCell(new Paragraph(item.getFunctionDescription(), content));
                    PdfPCell cell4 = new PdfPCell(new Paragraph(String.valueOf(item.getBudgetQuantity()), content));
                    PdfPCell cell5 = new PdfPCell(new Paragraph(item.getFunctionUnit(), content));
                    PdfPCell cell6 = new PdfPCell(new Paragraph(String.valueOf(item.getFunctionPrice()), content));
                    BigDecimal totalPrice = item.getFunctionPrice().multiply(BigDecimal.valueOf(item.getBudgetQuantity()));
                    PdfPCell cell7 = new PdfPCell(new Paragraph(String.valueOf(totalPrice), content));
                    //单元格对齐方式
                    cell1.setFixedHeight(20);
                    cell1.setHorizontalAlignment(Element.ALIGN_CENTER);
                    cell1.setVerticalAlignment(Element.ALIGN_MIDDLE);

					// 文字长度大于15的时候，设置表格行间距，底边距离
                    if (item.getFunctionName().length() > 15) {
                        cell2.setLeading(0f, 1.5f);
                        cell2.setPaddingBottom(10);
                    }
                    cell2.setHorizontalAlignment(Element.ALIGN_CENTER);
                    cell2.setVerticalAlignment(Element.ALIGN_MIDDLE);
					
					// 文字长度大于30的时候，设置表格行间距，底边距离
                    if (item.getFunctionDescription().length() > 30) {
                        cell3.setLeading(0f, 1.5f);
                        cell3.setPaddingBottom(10);
                    }
                    cell3.setHorizontalAlignment(Element.ALIGN_CENTER);
                    cell3.setVerticalAlignment(Element.ALIGN_MIDDLE);

                    cell4.setHorizontalAlignment(Element.ALIGN_CENTER);
                    cell4.setVerticalAlignment(Element.ALIGN_MIDDLE);

                    cell5.setHorizontalAlignment(Element.ALIGN_CENTER);
                    cell5.setVerticalAlignment(Element.ALIGN_MIDDLE);

                    cell6.setHorizontalAlignment(Element.ALIGN_CENTER);
                    cell6.setVerticalAlignment(Element.ALIGN_MIDDLE);

                    cell7.setHorizontalAlignment(Element.ALIGN_CENTER);
                    cell7.setVerticalAlignment(Element.ALIGN_MIDDLE);

                    table.addCell(cell1);
                    table.addCell(cell2);
                    table.addCell(cell3);
                    table.addCell(cell4);
                    table.addCell(cell5);
                    table.addCell(cell6);
                    table.addCell(cell7);

                    // 序号
                    index++;

                    modelTotal = modelTotal.add(totalPrice);
                }
                // 合计行
                PdfPCell cell1 = new PdfPCell(new Paragraph("合计", content));
                cell1.setFixedHeight(20);
                cell1.setHorizontalAlignment(Element.ALIGN_CENTER);
                cell1.setVerticalAlignment(Element.ALIGN_MIDDLE);
                // 空格
                PdfPCell cell2 = new PdfPCell(new Paragraph("", content));
                cell2.setFixedHeight(20);
                cell2.setHorizontalAlignment(Element.ALIGN_CENTER);
                cell2.setVerticalAlignment(Element.ALIGN_MIDDLE);
                // 数额
                PdfPCell cell3 = new PdfPCell(new Paragraph(String.valueOf(modelTotal), content));
                cell3.setFixedHeight(20);
                cell3.setHorizontalAlignment(Element.ALIGN_CENTER);
                cell3.setVerticalAlignment(Element.ALIGN_MIDDLE);
                table.addCell(cell1);
                table.addCell(cell2);
                table.addCell(cell2);
                table.addCell(cell2);
                table.addCell(cell2);
                table.addCell(cell2);
                table.addCell(cell3);

                detailTotal = detailTotal.add(modelTotal);
            }

            document.add(new Paragraph("\n"));
            document.add(new Paragraph("▋ " + functionInfo.getFunctionName(), content));
            document.add(table);
            document.add(new Paragraph("\n"));

            if (matchList.size() == 0) {
                document.add(new Paragraph("暂无数据", content));
            }
        }

        document.add(new Paragraph("\n"));
        document.add(new Paragraph("总计：" + detailTotal + "元", content));

        // 加水印
        PdfContentByte waterMar = pdfWriter.getDirectContentUnder();
        String text = "天天想辞职月月拿全勤";
        addTextFullWaterMark(waterMar, text, bfChinese);

        document.close();
    } catch (DocumentException e) {
        e.printStackTrace();
        log.error("导出pdf失败:{}", e);
    }
}

/**
 * 给表格添加表头
 *
 * @param table
 * @param content
 * @param titleList
 */
public void addTableTitle(PdfPTable table, Font content, String[] titleList) {
    PdfPCell cell = null;
    for (String title : titleList) {
        cell = new PdfPCell(new Paragraph(title, content));
        cell.setVerticalAlignment(Element.ALIGN_MIDDLE);
        cell.setHorizontalAlignment(Element.ALIGN_CENTER);
        cell.setFixedHeight(20);
        cell.setNoWrap(false);
        table.addCell(cell);
    }
}

/**
 * 给pdf添加文字水印（平铺）
 *
 * @param waterMar
 * @param text     水印文本
 * @throws Exception
 */
public static void addTextFullWaterMark(PdfContentByte waterMar, String text, BaseFont bf) {
    waterMar.beginText();

    PdfGState gs = new PdfGState();
    // 设置填充字体不透明度为0.2f
    gs.setFillOpacity(0.2f);
    waterMar.setFontAndSize(bf, 20);
    // 设置透明度
    waterMar.setGState(gs);
    // 设置水印对齐方式 水印内容 X坐标 Y坐标 旋转角度
    for (int x = 0; x <= 900; x += 200) {
        for (int y = -50; y <= 800; y += 200) {
            waterMar.showTextAligned(Element.ALIGN_RIGHT, text, x, y, 35);
        }
    }

    // 设置水印颜色
    waterMar.setColorFill(BaseColor.GRAY);

    //结束设置
    waterMar.endText();
    waterMar.stroke();
}