<!-- pdfbox -->
    <dependency>
      <groupId>org.apache.pdfbox</groupId>
      <artifactId>pdfbox</artifactId>
      <version>2.0.11</version>
    </dependency>
    <!-- docx4j -->
    <dependency>
      <groupId>org.docx4j</groupId>
      <artifactId>docx4j</artifactId>
      <version>3.3.7</version>
    </dependency>
    <dependency>
      <groupId>org.apache.xmlgraphics</groupId>
      <artifactId>batik-util</artifactId>
      <version>1.10</version>
    </dependency>
    <dependency>
      <groupId>org.docx4j</groupId>
      <artifactId>docx4j-export-fo</artifactId>
      <version>3.3.6</version>
    </dependency>
    <!-- https://mvnrepository.com/artifact/dom4j/dom4j -->
    <dependency>
      <groupId>dom4j</groupId>
      <artifactId>dom4j</artifactId>
      <version>1.6.1</version>
    </dependency>
    <!-- image -->
    <dependency>
      <groupId>net.coobird</groupId>
      <artifactId>thumbnailator</artifactId>
      <version>0.4.8</version>
    </dependency>
    <!-- json -->
    <dependency>
      <groupId>com.alibaba</groupId>
      <artifactId>fastjson</artifactId>
      <version>1.2.47</version>
    </dependency>

Map<String, Object> map = new HashMap<>();
map.put("name", "小明");
map.put("address", "北京市朝陽區(qū)");
map.put("email", "xiaoming@abc.com");
StringWriter stringWriter = new StringWriter();
BufferedWriter writer = new BufferedWriter(stringWriter);
template.process(map, writer);
String xmlStr = stringWriter.toString();

ByteArrayInputStream in = new ByteArrayInputStream(xmlStr.getBytes());
WordprocessingMLPackage wordMLPackage = WordprocessingMLPackage.load(in);

String outputfilepath = "/Users/xiaoming/簡(jiǎn)歷.pdf";
Docx4J.toPDF(wordMLPackage, new FileOutputStream(new File(outputfilepath)));

String folderName = "/Users/xiaoming/pdfs";
String destPath = "/Users/xiaoming/all.pdf";
PDFMergerUtility mergePdf = new PDFMergerUtility();
String[] filesInFolder = getFiles(folderName);
Arrays.sort(filesInFolder, new Comparator<String>() {
   @Override
   public int compare(String o1, String o2) {
     return o1.compareTo(o2);
   }
});
for (int i = 0; i < filesInFolder.length; i++) {
   mergePdf.addSource(folderName + File.separator + filesInFolder[i  ]);
}
mergePdf.setDestinationFileName(destPath);
mergePdf.mergeDocuments(MemoryUsageSetting.setupMainMemoryOnly());