需求：
給文書統一生成一個搞頭文件，文件內容基本是一樣的。
用freemarker生成docx文檔
一、生成一個docx結尾的word模板，然后把文檔的后綴docx改成zip，zip里會有生成很多文件。如下圖：

然后打開word文件夾，如下圖：

把document.xml拿出來，把后綴xml改成ftl，然后把里面的內容（在線格式化xml）格式化一下，把一些可變的參數做成變量。
二、在resources文件夾下創建wordTemplates文件夾，里面放剛才的zip和改名的gtwj.ftl文件。
三、替換word模板類：

import freemarker.template.Configuration;
import freemarker.template.Template;
import freemarker.template.TemplateException;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.io.*;
import java.util.Map;
import java.util.zip.ZipEntry;
import java.util.zip.ZipInputStream;
import java.util.zip.ZipOutputStream;

public class ZipUtils {

    private static final Logger logger = LoggerFactory.getLogger(ZipUtils.class);
    /**
     * 替換document , header1
     *
     * @param zipInputStream  zip文件的zip輸入流
     * @param zipOutputStream 輸出的zip輸出流
     * @param bodyOs        要替換的 word內容流
     */
    public static void replaceItem(ZipInputStream zipInputStream, ZipOutputStream zipOutputStream,
                                   ByteArrayOutputStream bodyOs) {

        String bodyname = "word/document.xml";
        //
        if (null == zipInputStream || null == zipOutputStream || null == bodyOs ) {
            return;
        }
        ZipEntry entryIn;
        try {
            while ((entryIn = zipInputStream.getNextEntry()) != null) {
                String entryName = entryIn.getName();
                ZipEntry entryOut = new ZipEntry(entryName);
                // 只使用 name
                zipOutputStream.putNextEntry(entryOut);
                if (entryName.equals(bodyname)) {
                    // 使用替換流 替換word內容
                    byte[] buf = bodyOs.toByteArray();
                    zipOutputStream.write(buf,0,buf.length);
                }
                else {
                    // 緩沖區
                    byte[] buf = new byte[8 * 1024];
                    int len;
                    // 輸出普通Zip流
                    while ((len = (zipInputStream.read(buf))) > 0) {
                        zipOutputStream.write(buf, 0, len);
                    }
                }
                // 關閉此 entry
                zipOutputStream.closeEntry();

            }
        } catch (IOException e) {
            logger.error("zip文件的zip輸入流失敗:", e);
        } finally {
            close(bodyOs);
            close(zipInputStream);
            close(zipOutputStream);
        }
    }
    /**
     * 包裝輸入流
     */
    public static ZipInputStream wrapZipInputStream(InputStream inputStream) {
        ZipInputStream zipInputStream = new ZipInputStream(inputStream);
        return zipInputStream;
    }

    /**
     * 包裝輸出流
     */
    public static ZipOutputStream wrapZipOutputStream(OutputStream outputStream) {
        ZipOutputStream zipOutputStream = new ZipOutputStream(outputStream);
        return zipOutputStream;
    }

    private static void close(InputStream inputStream) {
        if (null != inputStream) {
            try {
                inputStream.close();
            } catch (IOException e) {
                logger.error("關閉流失敗:", e);
            }
        }
    }

    private static void close(OutputStream outputStream) {
        if (null != outputStream) {
            try {
                outputStream.flush();
                outputStream.close();
            } catch (IOException e) {
                logger.error("關閉流失敗:", e);
            }
        }
    }

    /**
     * 獲取絕對路徑
     * @return
     */
    public static String systemUrl(){
        if(System.getProperties().getProperty("os.name").toUpperCase().indexOf("WINDOWS") != -1){
            return "D:";
        }
        return "/temp";
    }

    public static  void wordAndDoc(Map<String, Object> dataMap,ByteArrayOutputStream byteArrayOutputStream) throws IOException {
        //word body
        String bodyName = "gtwjtest.ftl";
        ByteArrayOutputStream bodyOs =  writeFile(bodyName,dataMap);
        ZipInputStream zipInputStream = ZipUtils.wrapZipInputStream(ZipUtils.class.getResourceAsStream("/wordTemplates/gtwj.zip"));
        ZipOutputStream zipOutputStream = ZipUtils.wrapZipOutputStream(byteArrayOutputStream);
        ZipUtils.replaceItem(zipInputStream, zipOutputStream, bodyOs);

    }

    public static  void word(Map<String, Object> dataMap,ByteArrayOutputStream byteArrayOutputStream) throws IOException {
        //word body
        String bodyName = "gtwj.ftl";
        ByteArrayOutputStream bodyOs =  writeFile(bodyName,dataMap);
        ZipInputStream zipInputStream = ZipUtils.wrapZipInputStream(ZipUtils.class.getResourceAsStream("/wordTemplates/gtwj.zip"));
        ZipOutputStream zipOutputStream = ZipUtils.wrapZipOutputStream(byteArrayOutputStream);
        ZipUtils.replaceItem(zipInputStream, zipOutputStream, bodyOs);

    }
    public static  String wordFile(Map<String, Object> dataMap,String docxUrl) throws IOException {
        String bodyName = "gtwj.ftl";
        ByteArrayOutputStream bodyOs =  writeFile(bodyName,dataMap);
        ZipInputStream zipInputStream = ZipUtils.wrapZipInputStream(ZipUtils.class.getResourceAsStream("/wordTemplates/gtwj.zip")); //D:\zip\月度用電報告.zip
        ZipOutputStream zipOutputStream = ZipUtils.wrapZipOutputStream(new FileOutputStream(new File(docxUrl)));
        ZipUtils.replaceItem(zipInputStream, zipOutputStream, bodyOs);
        return docxUrl;
    }
    /**
     * @Description  生成帶數據的模板
     * @Param
     */
    public static  ByteArrayOutputStream writeFile(String templateName,Map<String, Object> dataMap) throws IOException {
        Configuration configuration = new Configuration(Configuration.VERSION_2_3_28);
        configuration.setClassForTemplateLoading(ZipUtils.class, "/wordTemplates/");
        Template template = configuration.getTemplate(templateName);
        ByteArrayOutputStream os = new ByteArrayOutputStream();
        Writer out = new BufferedWriter(new OutputStreamWriter(os),10240);
        try {
            template.process(dataMap,out);
        } catch (TemplateException e) {
            logger.error("生成帶數據的模板失敗:", e);
        }finally {
            if(out != null ){
                out.close();
            }
        }
        return os;
    }
    /**
     * @Description  生成帶數據的模板
     * @Param
     */
    public static  void writeFile(String outFilePath,String templateName,Map<String, Object> dataMap) throws IOException {
        Configuration configuration = new Configuration(Configuration.VERSION_2_3_28);

        configuration.setClassForTemplateLoading(ZipUtils.class, "/ftl");
        Template template = configuration.getTemplate(templateName);
        File docFile = new File(outFilePath);
        FileOutputStream fos = new FileOutputStream(docFile);
        Writer out = new BufferedWriter(new OutputStreamWriter(fos),10240);
        try {
            template.process(dataMap,out);
        } catch (TemplateException e) {
            logger.error("生成帶數據的模板失敗:", e);
        }finally {
            if(out != null ){
                out.close();
            }
        }
    }
    /**
     * @Description 判斷文件夾是否存在 不存在就創建
     * @Param:
     * @return:
     */
    private static void isChartPathExist(String dirPath) {
        File file = new File(dirPath);
        if (!file.exists()) {
            file.mkdirs();
        }
        System.out.println(file.exists()+"  dirPath  "+dirPath);
    }
    public static void main(String[] args) {
//        String templatePath =ZipUtils.class.getResource("/").getPath()+ "/ftl";
//        System.out.println(templatePath);
//        isChartPathExist("D:\\zip\\123");
        File file = new File("F:\\word\\gtwj.pdf");
        if(file.exists()){
            if(file.isFile()){
                boolean b = file.delete();
                if (b) {
                    logger.info("成功");
                }
            }
        }
    }
}

四、項目里引入jar包如下：

        <dependency>
			<groupId>org.freemarker</groupId>
			<artifactId>freemarker</artifactId>
			<version>2.3.28</version>
		</dependency>

五、我用到的方法 ZipUtils.word(map, byteArrayOutputStream);其中map就是變量。