环境准备

开发环境

java8,SpringBoot 2.1.4，字符集GBK

字体

宋体--simsun.ttf

pom依赖

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-freemarker</artifactId>
</dependency>
<dependency>
    <groupId>com.itextpdf</groupId>
    <artifactId>kernel</artifactId>
    <version>7.0.3</version>
</dependency>
<dependency>
    <groupId>com.itextpdf</groupId>
    <artifactId>io</artifactId>
    <version>7.0.3</version>
</dependency>
<dependency>
    <groupId>com.itextpdf</groupId>
    <artifactId>forms</artifactId>
    <version>7.0.3</version>
</dependency>
<!-- 解决中文字体问题 -->
<dependency>
    <groupId>com.itextpdf</groupId>
    <artifactId>font-asian</artifactId>
    <version>7.0.3</version>
</dependency>
<dependency>
    <groupId>com.itextpdf</groupId>
    <artifactId>itextpdf</artifactId>
    <version>5.5.13</version>
</dependency>
<dependency>
    <groupId>com.itextpdf.tool</groupId>
    <artifactId>xmlworker</artifactId>
    <version>5.5.13</version>
</dependency>

模板生成PDF

将模板转换为html

从文件读取模板

/**
  * 初始化freemarker配置
  * templateRoot：模板文件根目录
  */
Configuration freemarkerCfg = initFreemarkerCfg(templateRoot);
/**
  * 将模板转换为HTML字符串
  */
String content = freeMarkerRender(data, freemarkerCfg, htmlTemplate, charSet);

private static Configuration initFreemarkerCfg(String templateRoot) {
   Configuration freemarkerCfg = new Configuration();
   try {
      freemarkerCfg.setDirectoryForTemplateLoading(new File(templateRoot));
   } catch (IOException e) {
      log.error("模板根路径获取失败!" + templateRoot, e);
      throw new RuntimeException("模板根路径获取失败!" + templateRoot,e);
   }
   return freemarkerCfg;
}

/**
  * data 需要注入模板的数据
  * freemarkerCfg freemarker配置
  * htmlTmp 模板名称
  * charSet 字符集 linux下使用UTF-8,windows下使用GBK，否则会出现中文乱码，模板文件的文件编码和声明编码同样需要保持一致
  */
private static String freeMarkerRender(Map<String, Object> data, Configuration freemarkerCfg, String htmlTmp,String charSet) {
   try (Writer out = new StringWriter();) {
      Template template = freemarkerCfg.getTemplate(htmlTmp);
      template.setEncoding(charSet);
      template.process(data, out);
      out.flush();
      return out.toString();
   } catch (Exception e) {
      log.error("HTML加载数据失败!", e);
      throw new RuntimeException("HTML加载数据失败!", e);
   }
}

从流读取模板

/**
  * data 需要注入模板的数据
  * fileName 文件名称
  * inputStream 模板文件流
  * charSet 字符集 linux下使用UTF-8,windows下使用GBK，否则会出现中文乱码，模板文件的文件编码和声明编码同样需要保持一致
  */
private static String freeMarkerRender(Map<String, Object> data, String fileName, InputStream inputStream,
      String charSet) {
   try (Writer out = new StringWriter();
         InputStreamReader inputStreamReader = new InputStreamReader(inputStream);) {
      Configuration configuration = new Configuration();
      Template template = new Template(fileName, inputStreamReader, configuration);
      template.setEncoding(charSet);
      template.process(data, out);
      out.flush();
      return out.toString();
   } catch (Exception e) {
      log.debug("HTML加载数据失败!", e);
      throw new RuleException(ErrCodeFile.CO_HTML_TEMPLATE_CONVERT_ERROR);
   }
}

生成PDF

/**
  * htmlContent 通过freemarker生成的html
  * fontPath 字体文件路径
  * ByteArrayOutputStream pdf文件流
  */
private static ByteArrayOutputStream htmlToPdf(String htmlContent, String fontPath) {
   try {
      ByteArrayOutputStream output = new ByteArrayOutputStream();
      ITextRenderer render = new ITextRenderer();
      ITextFontResolver fontResolver = render.getFontResolver();
      fontResolver.addFont(fontPath, BaseFont.IDENTITY_H, BaseFont.NOT_EMBEDDED);
      render.setDocumentFromString(htmlContent);
      render.getSharedContext().setBaseURL(BASE_URL);
      render.layout();
      render.createPDF(output);
      return output;
   } catch (Exception e) {
      log.debug("html转换pdf失败!", e);
      throw new RuntimeException("html转换pdf失败!", e);
   }
}

添加水印和页码

从文件获取水印

/**
  * outputStream 生成的pdf流
  * waterMarkPath 水印文件路径
  * fontPath 字体路径
  * OutputStream pdf文件流
  */
private static OutputStream addWaterImage(ByteArrayOutputStream outputStream, String waterMarkPath,
      String fontPath) {
   BaseFont baseFont = createFont(fontPath);
   try (InputStream input = new ByteArrayInputStream(outputStream.toByteArray());) {
      ByteArrayOutputStream output = new ByteArrayOutputStream();
      PdfReader reader = new PdfReader(input);
      PdfStamper stamp = new PdfStamper(reader, output);
      PdfContentByte contentByte = null;
      int n = reader.getNumberOfPages();
      Image logo = null;
      if(StringUtils.isNotBlank(waterMarkPath)){
          logo = Image.getInstance(waterMarkPath);
      }
      for (int i = 1; i <= n; i++) {
         contentByte = stamp.getUnderContent(i);
         Rectangle rectangle = reader.getPageSize(i);
         float width = rectangle.getWidth();
         float height = rectangle.getHeight();
         if(logo != null){
            logo.setAbsolutePosition(width / 2 - logo.getWidth() / 2, height / 2);
            contentByte.addImage(logo);
            contentByte.saveState();
         }
         String text = "第 " + i + " 页 /共 " + n + " 页";
         contentByte.beginText();
         contentByte.setFontAndSize(baseFont, 12);
         contentByte.showTextAligned(Element.ALIGN_CENTER, text, (width / 2) - 6, 15, 0);
         contentByte.endText();
      }
      reader.close();
      stamp.close();
      return output;
   } catch (Exception e) {
      log.debug("添加水印和页码失败," + waterMarkPath, e);
      throw new RuntimeException("添加水印和页码失败," + waterMarkPath, e);
   }
}

private static BaseFont createFont(String fontPath) {
   try {
      return BaseFont.createFont(fontPath, BaseFont.IDENTITY_H, BaseFont.NOT_EMBEDDED);
   } catch (Exception e) {
      log.debug("字体读取失败," + fontPath, e);
      throw new RuntimeException("字体读取失败," + fontPath, e);
   }
}

从流获取水印

/**
  * outputStream 生成的pdf流
  * waterMarkPath 水印流
  * fontPath 字体路径
  * OutputStream pdf文件流
  */
private static OutputStream addWaterImage(ByteArrayOutputStream outputStream, InputStream waterMarkPath,
      String fontPath) {
   BaseFont baseFont = createFont(fontPath);
   try (InputStream input = new ByteArrayInputStream(outputStream.toByteArray());) {
        ByteArrayOutputStream output = new ByteArrayOutputStream();
        PdfReader reader = new PdfReader(input);
        PdfStamper stamp = new PdfStamper(reader, output);
        PdfContentByte contentByte = null;
        int n = reader.getNumberOfPages();
        Image logo = null;
        if(waterMarkPath != null){
            byte[] waterMarkBytes = IOUtils.toByteArray(inputStream);
            logo = Image.getInstance(waterMarkBytes);
        }
        for (int i = 1; i <= n; i++) {
            contentByte = stamp.getUnderContent(i);
            Rectangle rectangle = reader.getPageSize(i);
            float width = rectangle.getWidth();
            float height = rectangle.getHeight();
            if(logo != null){
                logo.setAbsolutePosition(width / 2 - logo.getWidth() / 2, height / 2);
                contentByte.addImage(logo);
                contentByte.saveState();
            }
            String text = "第 " + i + " 页 /共 " + n + " 页";
            contentByte.beginText();
            contentByte.setFontAndSize(baseFont, 12);
            contentByte.showTextAligned(Element.ALIGN_CENTER, text, (width / 2) - 6, 15, 0);
            contentByte.endText();
        }
         reader.close();
         stamp.close();
        return output;
    } catch (Exception e) {
      log.debug("添加水印和页码失败," + waterMarkPath, e);
      throw new RuntimeException("添加水印和页码失败," + waterMarkPath, e);
    }
}

pdf加密码及权限设置

权限说明

权限	说明
ALLOW_PRINTING	文档允许打印
ALLOW_DEGRADED_PRINTING	允许用户打印文档，但不提供allow_printing质量（128位加密）
ALLOW_MODIFY_CONTENTS	允许用户修改内容，例如更改页面内容，或插入或删除页
ALLOW_ASSEMBLY	允许用户插入、删除和旋转页面和添加书签。页面的内容不能更改，除非也授予allow_modify_contents权限，（128位加密）
ALLOW_COPY	允许用户复制或以其他方式从文档中提取文本和图形，包括使用辅助技术。例如屏幕阅读器或其他可访问设备
ALLOW_SCREENREADERS	允许用户提取文本和图形以供易访问性设备使用，（128位加密）
ALLOW_MODIFY_ANNOTATIONS	允许用户添加或修改文本注释和交互式表单字段
ALLOW_FILL_IN	允许用户填写表单字段，（128位加密）

需要多个权限时，用|拼接即可

无水印页码

在生成PDF时添加权限及密码

private static ByteArrayOutputStream htmlToPdf(String htmlContent, String fontPath, String password, String adminPassword) {
   try {
      ByteArrayOutputStream output = new ByteArrayOutputStream();
      ITextRenderer render = new ITextRenderer();
      ITextFontResolver fontResolver = render.getFontResolver();
      setPDFEncryption(password, adminPassword, render);
      fontResolver.addFont(fontPath, BaseFont.IDENTITY_H, BaseFont.NOT_EMBEDDED);
      render.setDocumentFromString(htmlContent);
      render.getSharedContext().setBaseURL(BASE_URL);
      render.layout();
      render.createPDF(output);
      return output;
   } catch (Exception e) {
      log.debug("html转换pdf失败!", e);
      throw new RuleException(ErrCodeFile.CO_HTML_TO_PDF_FAILED);
   }
}

/** 用户权限,根据需求自己设置*/
private static final int PERMIT = PdfWriter.ALLOW_PRINTING;
/** pdf加密类型*/
private static final int ENCRYPTION_TYPE = PdfWriter.STANDARD_ENCRYPTION_128;
private static void setPDFEncryption(String password, String adminPassword,ITextRenderer render) {
    PDFEncryption pdfEncryption = new PDFEncryption();
    // 用户密码
    pdfEncryption.setUserPassword(password.getBytes());
    // 管理员密码
    pdfEncryption.setOwnerPassword(adminPassword.getBytes());
    // 用户权限
    pdfEncryption.setAllowedPrivileges(PERMIT);
    // 加密类型
    pdfEncryption.setEncryptionType(ENCRYPTION_TYPE);
    render.setPDFEncryption(pdfEncryption);
}

有水印页码

在生成PDF时无需添加权限及密码，在添加水印及页码时添加

private static OutputStream addWaterImage(ByteArrayOutputStream outputStream, InputStream waterMarkPath,
      String fontPath, String password, String adminPassword) {
   BaseFont baseFont = createFont(fontPath);
   try (InputStream input = new ByteArrayInputStream(outputStream.toByteArray());) {
        ByteArrayOutputStream output = new ByteArrayOutputStream();
        PdfReader reader = new PdfReader(input);
        PdfStamper stamp = new PdfStamper(reader, output);
        // 用户密码，管理员密码，权限，加密类型
        stamp.setEncryption(password.getBytes(), adminPassword.getBytes(), PERMIT, ENCRYPTION_TYPE);
        PdfContentByte contentByte = null;
        int n = reader.getNumberOfPages();
        Image logo = null;
        if(waterMarkPath != null){
            byte[] waterMarkBytes = IOUtils.toByteArray(inputStream);
            logo = Image.getInstance(waterMarkBytes);
        }
        for (int i = 1; i <= n; i++) {
            contentByte = stamp.getUnderContent(i);
            Rectangle rectangle = reader.getPageSize(i);
            float width = rectangle.getWidth();
            float height = rectangle.getHeight();
            if(logo != null){
                logo.setAbsolutePosition(width / 2 - logo.getWidth() / 2, height / 2);
                contentByte.addImage(logo);
                contentByte.saveState();
            }
            String text = "第 " + i + " 页 /共 " + n + " 页";
            contentByte.beginText();
            contentByte.setFontAndSize(baseFont, 12);
            contentByte.showTextAligned(Element.ALIGN_CENTER, text, (width / 2) - 6, 15, 0);
            contentByte.endText();
        }
         reader.close();
         stamp.close();
        return output;
    } catch (Exception e) {
      log.debug("添加水印和页码失败," + waterMarkPath, e);
      throw new RuntimeException("添加水印和页码失败," + waterMarkPath, e);
    }
}

模板记录

1、字符集乱码问题

<meta http-equiv="Content-Type" content="text/html; charset=GBK"/>

（历史原因导致开发使用GBK字符集，UTF-8的情况暂时未知）charset应与Java代码中的传入的保持一致，同时ftl文件的字符集应与此保持一致，windows使用GBK，linux使用UTF-8，否则生成PDF乱码

2、img标签

<img src="${logoImage}" width="204"/>

img标签支持base64格式data:image/png;base64,

data:,文本数据
data:text/plain,文本数据
data:text/html,HTML代码
data:text/html;base64,base64编码的HTML代码
data:text/css,CSS代码
data:text/css;base64,base64编码的CSS代码
data:text/javascript,Javascript代码
data:text/javascript;base64,base64编码的Javascript代码
data:image/gif;base64,base64编码的gif图片数据
data:image/png;base64,base64编码的png图片数据
data:image/jpeg;base64,base64编码的jpeg图片数据
data:image/x-icon;base64,base64编码的icon图片数据

3、强制分页

<p style="margin: 0pt">
    <div style="page-break-before: always; clear: both"/>
</p>

4、 head记录

<head>
    <meta http-equiv="Content-Type" content="text/html; charset=GBK"/>
    <meta http-equiv="Content-Style-Type" content="text/css"/>
    <title>xxxx</title>
    <style type='text/css'>
        body {
            font-family: SimSun;
            padding-top: 50px;
        }

        @page {
            size: a4;
            @top-center {
                content: element(header);
            }
            @bottom-center {
                content: element(footer);
            }

        }

        div.header {
            display: block;
            /*text-align: center;*/
            position: running(header);
            width: 100%;
        }

        div.footer {
            display: block;
            text-align: center;
            position: running(footer);
            width: 100%;
        }

        .custom-page-start {
            margin-top: 50px;
        }

        table {
            border-collapse: collapse;
            margin: 0 auto;
            width: 100%;
        }

        td {
            border: #000000 solid 0.75pt;
            vertical-align: top;
            padding: 5pt;
        }

        p {
            line-height: 18pt;
            margin: 0pt 0pt 4pt;
        }

        span {
            font-size: 10pt;
        }

        @media print {
            table {
                page-break-after: auto
            }

            tr {
                page-break-inside: avoid;
                page-break-after: auto
            }

            td {
                page-break-inside: avoid;
                page-break-after: auto
            }

            thead {
                display: table-header-group
            }

            tfoot {
                display: table-footer-group
            }
        }       
    </style>
</head>

freemarker生成PDF文件