《SpringBoot2.0 实战》系列-整合FlyingSaucer + thymeleaf 实现模板文件转pdf打印

╰半夏微凉° 2023-07-08 02:37 2阅读 0赞

### 前言 ###

最近，接到一个模板打印pdf的任务，后来网上找了很多案例，本文做下记录。

### 如何开始 ###

添加依赖包

<dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-thymeleaf</artifactId>
    </dependency>
    
    <dependency>
        <groupId>org.xhtmlrenderer</groupId>
        <artifactId>flying-saucer-pdf</artifactId>
        <version>9.1.9</version>
    </dependency>

yml配置（可选，不配置默认也可）

spring:
      # thymeleaf
      thymeleaf:
        prefix: classpath:/templates/
        check-template-location: true
        suffix: .html
        encoding: UTF-8
        mode: HTML
        cache: false
        servlet:
          content-type: text/html

### 模板文件 ###

如下文件放置位置，文件都在我的开源项目中，文末有地址。

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L0hYTkxZVw_size_16_color_FFFFFF_t_70][]

pdfPage模板文件：

<!DOCTYPE html>
    <html xmlns:th="http://www.thymeleaf.org" xmlns:layout="http://www.w3.org/1999/xhtml" layout:decorator="layout">
    <head lang="en">
        <title>Spring Boot Demo - PDF</title>
        <style>
            @page {
                size: 210mm 297mm; /*设置纸张大小:A4(210mm 297mm)、A3(297mm 420mm) 横向则反过来*/
                margin: 0.25in;
                padding: 1em;
                @bottom-center{
                    content:"葫芦科技 © 版权所有";
                    font-family: SimSun;
                    font-size: 12px;
                    color:red;
                };
                @top-center { content: element(header) };
                @bottom-right{
                    content:"第" counter(page) "页  共 " counter(pages) "页";
                    font-family: SimSun;
                    font-size: 12px;
                    color:#000;
                };
            }
            body{font-family: 'SimSun'}
            h2{color: crimson}
            #myheader{
                width: 500px;
                height: 22px;
                border: 1px solid #000000;
            }
            table, th , td  {
                border: 1px solid grey;
                border-collapse: collapse;
                padding: 5px;
            }
            table tr:nth-child(odd) {
                background-color: #f1f1f1;
            }
            table tr:nth-child(even) {
                background-color: #ffffff;
            }
            #input1{
                border-bottom: 1px solid #000000;
            }
        </style>
    </head>
    
    
    <body style="font-family: 'SimSun'">
    <div>1.标题-中文</div>
    <h2 th:text="${title}"></h2>
    
    <div>2.按钮:按钮的边框需要写css渲染</div>
    <button class="a" style="border: 1px solid #000000"> click me t-p</button>
    <div id="divsub"></div>
    
    <div>3.普通div</div>
    <div id="myheader">Alice's Adventures in Wonderland</div>
    
    <div>4.图片 绝对定位到左上角(注意:图片必须用全路径或者http://开头的路径,否则无法显示)</div>
    <img th:src="${imageUrl}"/>
    
    <div>5.普通table表格</div>
    <div>
        <table style="width: 700px">
            <tr>
                <th>姓名</th>
                <th>昵称</th>
                <th>年龄</th>
            </tr>
            <tr th:each="info : ${demoList}">
                <td th:text="${info.name}"></td>
                <td th:text="${info.nick}"></td>
                <td th:text="${info.age}"></td>
            </tr>
        </table>
    
    </div>
    
    <div>6.input控件,边框需要写css渲染 (在模板中一般不用input,因为不存在输入操作)</div>
    <div>
        <label>姓名:</label>
        <input id="input1" aria-label="葫芦胡" type="text" value="葫芦胡"/>
    </div>
    </body>
    </html>

避坑：

> 测试的时候，模板文件中一定至少有一个：th:text="$\{xxx\}"，否则会报模板不存在
> 
> 图片路径需绝对路径，如：http://localhost:8088/hu/imgs/sg.jpg

### 核心处理类 ###

**工具类**

/**
     * pdf处理工具类
     *
     * @author gourd.hu
     * @version 1.0
     */
    @Slf4j
    public class PdfUtil {
    
        /**
         * 按模板和参数生成html字符串,再转换为flying-saucer识别的Document
         *
         * @param templateName 模板名称
         * @param variables   模板参数
         * @return Document
         */
        private static Document generateDoc(TemplateEngine templateEngine, String templateName, Map<String, Object> variables)  {
            // 声明一个上下文对象，里面放入要存到模板里面的数据
            final Context context = new Context();
            context.setVariables(variables);
            StringWriter stringWriter = new StringWriter();
            try(BufferedWriter writer = new BufferedWriter(stringWriter)) {
                templateEngine.process(templateName,context, writer);
                writer.flush();
                DocumentBuilder builder = DocumentBuilderFactory.newInstance().newDocumentBuilder();
                return builder.parse(new ByteArrayInputStream(stringWriter.toString().getBytes()));
            }catch (Exception e){
                ResponseEnum.TEMPLATE_PARSE_ERROR.assertFail(e);
            }
            return null;
        }
    
        /**
         * 核心: 根据freemarker模板生成pdf文档
         *
         * @param templateEngine 配置
         * @param templateName 模板名称
         * @param out          输出流
         * @param listVars     模板参数
         * @throws Exception 模板无法找到、模板语法错误、IO异常
         */
        private static void generateAll(TemplateEngine templateEngine, String templateName, OutputStream out, List<Map<String, Object>> listVars) throws Exception {
            // 断言参数不为空
            ResponseEnum.TEMPLATE_DATA_NULL.assertNotEmpty(listVars);
            ITextRenderer renderer = new ITextRenderer();
            //设置字符集(宋体),此处必须与模板中的<body style="font-family: SimSun">一致,区分大小写,不能写成汉字"宋体"
            ITextFontResolver fontResolver = renderer.getFontResolver();
            //避免中文为空设置系统字体
            fontResolver.addFont("static/fonts/simsun.ttf", BaseFont.IDENTITY_H, BaseFont.NOT_EMBEDDED);
    
            //根据参数集个数循环调用模板,追加到同一个pdf文档中
            //(注意:此处从1开始,因为第0是创建pdf,从1往后则向pdf中追加内容)
            for (int i = 0; i < listVars.size(); i++) {
                Document docAppend = generateDoc(templateEngine, templateName, listVars.get(i));
                renderer.setDocument(docAppend, null);
                //展现和输出pdf
                renderer.layout();
                if(i==0){
                    renderer.createPDF(out, false);
                }else {
                    //写下一个pdf页面
                    renderer.writeNextDocument();
                }
    
            }
            renderer.finishPDF(); //完成pdf写入
        }
    
        /**
         * pdf下载
         *
         * @param templateEngine   配置
         * @param templateName 模板名称
         * @param listVars     模板参数集
         * @param response     HttpServletResponse
         * @param fileName     下载文件名称
         */
        public static void download(TemplateEngine templateEngine, String templateName, List<Map<String, Object>> listVars, HttpServletResponse response, String fileName) {
            // 设置编码、文件ContentType类型、文件头、下载文件名
            response.setCharacterEncoding("utf-8");
            response.setContentType("multipart/form-data");
            try {
                response.setHeader("Content-Disposition", "attachment;fileName=" +
                        new String(fileName.getBytes("gb2312"), "ISO8859-1"));
            } catch (UnsupportedEncodingException e) {
                log.error(e.getMessage(), e);
            }
            try (ServletOutputStream out = response.getOutputStream()) {
                generateAll(templateEngine, templateName, out, listVars);
                out.flush();
            } catch (Exception e) {
                log.error(e.getMessage(), e);
            }
        }
    
        /**
         * pdf下载到特定位置
         *
         * @param templateEngine   配置
         * @param templateName 模板名称
         * @param listVars     模板参数集
         * @param filePath     下载文件路径
         */
        public static void save(TemplateEngine templateEngine, String templateName, List<Map<String, Object>> listVars, String filePath) {
            try (OutputStream out = new FileOutputStream(filePath);) {
                generateAll(templateEngine, templateName, out, listVars);
                out.flush();
            } catch (Exception e) {
                log.error(e.getMessage(), e);
            }
        }
    
        /**
         * pdf预览
         *
         * @param templateEngine   配置
         * @param templateName 模板名称
         * @param listVars     模板参数集
         * @param response     HttpServletResponse
         */
        public static void preview(TemplateEngine templateEngine, String templateName, List<Map<String, Object>> listVars, HttpServletResponse response) {
            try (ServletOutputStream out = response.getOutputStream()) {
                generateAll(templateEngine, templateName, out, listVars);
                out.flush();
            } catch (Exception e) {
                log.error(e.getMessage(), e);
            }
        }
    }

**Controller**

/**
     * pdf预览、下载
     *
     * @author gourd.hu
     * @version 1.0
     */
    @RestController
    @RequestMapping(value = "/pdf")
    @Api(tags = "pdf测试API", description = "pdf功能")
    public class PdfController {
    
        @Autowired
        private TemplateEngine templateEngine;
    
        @Value("${pdf.windowsFileTempLoc}")
        private String pdfWindowsPath;
    
        @Value("${pdf.linuxFileTempLoc}")
        private String pdfLinuxPath;
        
    /**
     * 文档预览、下载
     *
     * @author gourd.hu
     * @version 1.0
     */
    @RestController
    @RequestMapping(value = "/document")
    @Api(tags = "文档预览、下载API")
    public class DocumentController {
    
        @Autowired
        private TemplateEngine templateEngine;
    
        @Value("${pdf.windowsFileTempLoc}")
        private String pdfWindowsPath;
    
        @Value("${pdf.linuxFileTempLoc}")
        private String pdfLinuxPath;
    
        /**
         * pdf预览
         *
         * @param response HttpServletResponse
         */
        @GetMapping(value = "/pdf/preview")
        @ApiOperation(value="pdf预览")
        public void preview(HttpServletResponse response) {
            // 构造freemarker模板引擎参数,listVars.size()个数对应pdf页数
            List<Map<String,Object>> listVars = new ArrayList<>();
            Map<String,Object> variables = new HashMap<>(4);
            variables.put("title","测试预览PDF!");
            variables.put("imageUrl",sslEnabled?"https://localhost:10001/imgs/sg.jpg":"http://localhost:10001/imgs/sg.jpg");
            List<Map<String,String>> demoList = new ArrayList<>();
            Map<String,String> demoMap = new HashMap<>(8);
            demoMap.put("name","哈哈");
            demoMap.put("nick","娃娃");
            demoMap.put("age","19");
            Map<String,String> demoMap2 = new HashMap<>(8);
            demoMap2.put("name","天天");
            demoMap2.put("nick","饭饭");
            demoMap2.put("age","14");
            demoList.add(demoMap);
            demoList.add(demoMap2);
            variables.put("demoList",demoList);
            Map<String,Object> variables2 = new HashMap<>(4);
            variables2.put("title","测试预览PDF2!");
            listVars.add(variables);
            listVars.add(variables2);
    
            PdfUtil.preview(templateEngine,"pdfPage",listVars,response);
        }
    
        /**
         * pdf下载
         *
         * @param response HttpServletResponse
         */
        @GetMapping(value = "/pdf/download")
        @ApiOperation(value="pdf下载")
        public void download(HttpServletResponse response) {
            List<Map<String,Object>> listVars = new ArrayList<>(1);
            Map<String,Object> variables = new HashMap<>(4);
            variables.put("title","测试下载PDF!");
            variables.put("imageUrl",sslEnabled?"https://localhost:10001/imgs/sg.jpg":"http://localhost:10001/imgs/sg.jpg");
            List<Map<String,String>> demoList = new ArrayList<>();
            Map<String,String> demoMap = new HashMap<>(8);
            demoMap.put("name","哈哈");
            demoMap.put("nick","娃娃");
            demoMap.put("age","19");
            Map<String,String> demoMap2 = new HashMap<>(8);
            demoMap2.put("name","天天");
            demoMap2.put("nick","饭饭");
            demoMap2.put("age","14");
            demoList.add(demoMap);
            demoList.add(demoMap2);
            variables.put("demoList",demoList);
            listVars.add(variables);
            PdfUtil.download(templateEngine,"pdfPage",listVars,response,"测试打印.pdf");
        }
    
        /**
         * pdf下载到特定位置
         *
         */
        @GetMapping(value = "/pdf/save")
        @ApiOperation(value="pdf下载到特定位置")
        public void save() {
            List<Map<String,Object>> listVars = new ArrayList<>(1);
            Map<String,Object> variables = new HashMap<>(4);
            variables.put("title","测试下载PDF!");
            variables.put("imageUrl",sslEnabled?"https://localhost:10001/imgs/sg.jpg":"http://localhost:10001/imgs/sg.jpg");
            List<Map<String,String>> demoList = new ArrayList<>();
            Map<String,String> demoMap = new HashMap<>(8);
            demoMap.put("name","哈哈");
            demoMap.put("nick","娃娃");
            demoMap.put("age","19");
            Map<String,String> demoMap2 = new HashMap<>(8);
            demoMap2.put("name","天天");
            demoMap2.put("nick","饭饭");
            demoMap2.put("age","14");
            demoList.add(demoMap);
            demoList.add(demoMap2);
            variables.put("demoList",demoList);
            listVars.add(variables);
            // pdf文件下载位置
            String pdfPath = CommonUtil.isLinux() ? pdfLinuxPath : pdfWindowsPath;
            PdfUtil.save(templateEngine,"pdfPage",listVars,pdfPath);
        }
    }
    }

### 演示效果 ###

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L0hYTkxZVw_size_16_color_FFFFFF_t_70 1][]

## 结语 ##

至此，pdf打印功能就完成了，如果本文有错误的地方，欢迎评论指正。

===============================================

代码均已上传至本人的开源项目

![20191230131831499.jpeg][]

cloud-plus：[https://blog.csdn.net/HXNLYW/article/details/104635673][https_blog.csdn.net_HXNLYW_article_details_104635673]

[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L0hYTkxZVw_size_16_color_FFFFFF_t_70]: https://img-blog.csdnimg.cn/20200522135700170.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L0hYTkxZVw==,size_16,color_FFFFFF,t_70
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L0hYTkxZVw_size_16_color_FFFFFF_t_70 1]: https://img-blog.csdnimg.cn/20200525123650247.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L0hYTkxZVw==,size_16,color_FFFFFF,t_70
[20191230131831499.jpeg]: https://img-blog.csdnimg.cn/20191230131831499.jpeg
[https_blog.csdn.net_HXNLYW_article_details_104635673]: https://blog.csdn.net/HXNLYW/article/details/104635673