SpringBoot使用freemarker导出word文件方法详解

<!--freemarker-->
<dependency>
    <groupId>org.freemarker</groupId>
    <artifactId>freemarker</artifactId>
    <version>2.3.30</version>
</dependency>

/**
     * 根据ftl模板模板下载word文档
     */
@GetMapping("/downloadWord")
public void downloadWord(HttpServletResponse response){
    Map<String, Object> map = new HashMap<>();
    map.put("username", "王天霸");//姓名
    map.put("idno", "429004199601521245");//身份证号
    map.put("hireDate", "2021年12月12日");//入职日期
    map.put("work", "Java软件工程师");//职务
    map.put("endDate", "2022年11月25日");//离职日期
    map.put("imageData", Tools.getBase64ByPath("D:\\demo\\test.png"));//盖章Base64数据（不包含头信息）
    try {
        FreemarkerExportWordUtil.exportWord(response, map, "离职证明.doc", "EmploymentSeparationCertificate.ftl");
    } catch (IOException e) {
        e.printStackTrace();
    }
}

package org.wujiangbo.utils;
import org.wujiangbo.domain.user.User;
import sun.misc.BASE64Encoder;
import java.io.*;
import java.util.ArrayList;
import java.util.List;
/**
 * <p>工具类</p>
 */
public class Tools {
    /**
     * 获得指定图片文件的base64编码数据
     * @param filePath 文件路径
     * @return base64编码数据
     */
    public static String getBase64ByPath(String filePath) {
        if(!hasLength(filePath)){
            return "";
        }
        File file = new File(filePath);
        if(!file.exists()) {
            return "";
        }
        InputStream in = null;
        byte[] data = null;
        try {
            in = new FileInputStream(file);
        } catch (FileNotFoundException e1) {
            e1.printStackTrace();
        }
        try {
            assert in != null;
            data = new byte[in.available()];
            in.read(data);
            in.close();
        } catch (IOException e) {
            e.printStackTrace();
        }
        BASE64Encoder encoder = new BASE64Encoder();
        return encoder.encode(data);
    }
    /**
     * @desc 判断字符串是否有长度
     */
    public static boolean hasLength(String str) {
        return org.springframework.util.StringUtils.hasLength(str);
    }
}

package org.wujiangbo.utils;
import freemarker.template.Configuration;
import freemarker.template.Template;
import freemarker.template.Version;
import javax.servlet.http.HttpServletResponse;
import java.io.*;
import java.net.URLEncoder;
import java.nio.charset.StandardCharsets;
import java.util.Map;
/**
 * 模板word导出，工具类
 */
public class FreemarkerExportWordUtil {
    private static Configuration configuration = null;
    static {
        configuration = new Configuration(new Version("2.3.0"));
        configuration.setDefaultEncoding("utf-8");
        //获取模板路径    setClassForTemplateLoading 这个方法默认路径是webRoot 路径下
        configuration.setClassForTemplateLoading(FreemarkerExportWordUtil.class, "/templates");
    }
    private FreemarkerExportWordUtil() {
        throw new AssertionError();
    }
    /**
     * 根据 /resources/templates 目录下的ftl模板文件生成文件并写到客户端进行下载
     * @param response HttpServletResponse
     * @param map 数据集合
     * @param fileName 用户下载到的文件名称
     * @param ftlFileName ftl模板文件名称
     * @throws IOException
     */
    public static void exportWord(HttpServletResponse response, Map map, String fileName, String ftlFileName) throws IOException {
        Template freemarkerTemplate = configuration.getTemplate(ftlFileName);
        // 调用工具类的createDoc方法生成Word文档
        File file = createDoc(map, freemarkerTemplate);
        //将word文档写到前端
        download(file.getAbsolutePath(), response, fileName);
    }
    private static File createDoc(Map<?, ?> dataMap, Template template) {
        //临时文件
        String name = "template.doc";
        File f = new File(name);
        Template t = template;
        try {
            // 这个地方不能使用FileWriter因为需要指定编码类型否则生成的Word文档会因为有无法识别的编码而无法打开
            Writer w = new OutputStreamWriter(new FileOutputStream(f), "utf-8");
            t.process(dataMap, w);
            w.close();
        } catch (Exception ex) {
            ex.printStackTrace();
            throw new RuntimeException(ex);
        }
        return f;
    }
    //下载文件的公共方法
    public static void download(String filePath, HttpServletResponse response, String fileName) {
        try {
            setAttachmentResponseHeader(response, fileName);
        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
        }
        try(
                BufferedInputStream bis = new BufferedInputStream(new FileInputStream(filePath));
                // 输出流
                BufferedOutputStream bos = new BufferedOutputStream(response.getOutputStream());
        ){
            byte[] buff = new byte[1024];
            int len = 0;
            while ((len = bis.read(buff)) > 0) {
                bos.write(buff, 0, len);
            }
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
    /**
     * 下载文件名重新编码
     * @param response 响应对象
     * @param realFileName 真实文件名
     * @return
     */
    public static void setAttachmentResponseHeader(HttpServletResponse response, String realFileName) throws UnsupportedEncodingException
    {
        String percentEncodedFileName = percentEncode(realFileName);
        StringBuilder contentDispositionValue = new StringBuilder();
        contentDispositionValue.append("attachment; filename=")
                .append(percentEncodedFileName)
                .append(";")
                .append("filename*=")
                .append("utf-8''")
                .append(percentEncodedFileName);
        response.addHeader("Access-Control-Allow-Origin", "*");
        response.addHeader("Access-Control-Expose-Headers", "Content-Disposition,download-filename");
        response.setHeader("Content-disposition", contentDispositionValue.toString());
        response.setHeader("download-filename", percentEncodedFileName);
    }
    /**
     * 百分号编码工具方法
     *
     * @param s 需要百分号编码的字符串
     * @return 百分号编码后的字符串
     */
    public static String percentEncode(String s) throws UnsupportedEncodingException
    {
        String encode = URLEncoder.encode(s, StandardCharsets.UTF_8.toString());
        return encode.replaceAll("\\+", "%20");
    }
}

<dependency>
    <groupId>com.documents4j</groupId>
    <artifactId>documents4j-local</artifactId>
    <version>1.0.3</version>
</dependency>
<dependency>
    <groupId>com.documents4j</groupId>
    <artifactId>documents4j-transformer-msoffice-word</artifactId>
    <version>1.0.3</version>
</dependency>

/**
     * word文档转成PDF文档
     * @param wordPath word文档路径
     * @param pdfPath pdf文档路径
     */
public static void word2pdf(String wordPath, String pdfPath){
    File inputWord = new File(wordPath);
    File outputFile = new File(pdfPath);
    InputStream docxInputStream = null;
    OutputStream outputStream = null;
    IConverter converter = null;
    try  {
        docxInputStream = new FileInputStream(inputWord);
        outputStream = new FileOutputStream(outputFile);
        converter = LocalConverter.builder().build();
        converter.convert(docxInputStream).as(DocumentType.DOCX).to(outputStream).as(DocumentType.PDF).execute();
        outputStream.close();
    } catch (Exception e) {
        e.printStackTrace();
        log.error("word文档转成PDF文档时，发生异常：{}", e.getLocalizedMessage());
    } finally {
        //关闭资源
        try {
            if(docxInputStream != null){
                docxInputStream.close();
            }
            if(outputStream != null){
                outputStream.close();
            }
            if(converter != null){
                converter.shutDown();
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}