Java项目如何导出数据为 PDF 文件？

一个小需求，需要将页面上的数据导出为PDF，正常情况下这个需求需要让前端来做，但是现在上面让咱们后端来做，也没问题。

直接上代码

一、代码结构如下

二、代码说明

1、添加依赖 pom.xml

<dependency>
    <groupId>com.openhtmltopdf</groupId>
    <artifactId>openhtmltopdf-core</artifactId>
    <version>1.0.0</version>
</dependency>
<dependency>
    <groupId>com.openhtmltopdf</groupId>
    <artifactId>openhtmltopdf-pdfbox</artifactId>
    <version>1.0.0</version>
</dependency>
<dependency>
    <groupId>org.thymeleaf</groupId>
    <artifactId>thymeleaf</artifactId>
    <version>3.0.11.RELEASE</version>
</dependency>
<dependency>
    <groupId>org.thymeleaf</groupId>
    <artifactId>thymeleaf-spring5</artifactId>
    <version>3.0.11.RELEASE</version>
</dependency>

2、HTML模板文件 audit_order_record.html

<!DOCTYPE html>
<html xmlns:th="http://www.thymeleaf.org" lang="en">
<head>
    <meta charset="UTF-8"/>
    <title th:text="${pdfFileName}"></title>
    <style>
        @page {
            size: A4;
            @top-center {
                content: element(header);
            }
            @bottom-center {
                content: '';
                font-family: 'stxihei', serif;
            }
        }
        html, body {
            font-family: 'stxihei', serif;
        }
        table {
            -fs-table-paginate: paginate;
            border-collapse: collapse;
        }
        #page-header {
            position: running(header);
            border-bottom: 1px solid #555;
            padding: 5px;
        }
        #page-header-text {
            font-size: 16px;
        }
        #page-header-num:after {
            float: right;
            text-align: right;
            content: counter(page) '/' counter(pages);
        }
        table {
            width: 100%;
            margin: auto 0;
        }
        table, td, th {
            border: 1px solid #555;
            padding: 10px;
            text-align: center;
        }
        th {
            background-color: #eff3fa;
            width: 200px;
        }
</style>
</head>
<body>
<div id="page-header">
    <span id="page-header-text">审批记录</span>
    <span id="page-header-num"></span>
</div>

<table>
    <tr>
        <th colspan="2">资源信息</th>
    </tr>
    <tr>
        <th>目录名称</th>
        <td>[[${resourceName}]]</td>
    </tr>
    <tr>
        <th>资源名称</th>
        <td>[[${infoName}]]</td>
    </tr>
    <tr>
        <th>资源类型</th>
        <td>[[${resourceType}]]</td>
    </tr>
    <tr>
        <th>数据提供方</th>
        <td>[[${resOrgName}]]</td>
    </tr>
    <tr>
        <th colspan="2">订阅信息</th>
    </tr>
    <tr>
        <th>资源需求方</th>
        <td>[[${orgName}]]</td>
    </tr>
    <tr>
        <th>需求方系统</th>
        <td>[[${systemName}]]</td>
    </tr>
    <tr>
        <th>联系人</th>
        <td>[[${linkMan}]]</td>
    </tr>
    <tr>
        <th>联系手机</th>
        <td>[[${linkPhone}]]</td>
    </tr>
    <tr>
        <th>申请日期</th>
        <td>[[${orderDate}]]</td>
    </tr>
    <tr>
        <th>申请理由</th>
        <td>[[${orderReason}]]</td>
    </tr>
    <tr>
        <th colspan="2">审核信息</th>
    </tr>
    <tr>
        <th>审核人</th>
        <td>[[${prejuUserName}]]</td>
    </tr>
    <tr>
        <th>审核结果</th>
        <td>[[${prejuResult}]]</td>
    </tr>
    <tr>
        <th>审核日期</th>
        <td>[[${prejuDate}]]</td>
    </tr>
    <tr>
        <th>审核意见</th>
        <td>[[${prejuSuggest}]]</td>
    </tr>
</table>
</body>
</html>

3、添加字体

将字体文件 STXIHEI.TTF 放在 pdf/fonts 下面

4、PDF 导出工具类

 
package com.libin.pdf.demo.util;

import com.openhtmltopdf.pdfboxout.PdfRendererBuilder;
import org.springframework.util.ResourceUtils;
import org.thymeleaf.context.Context;
import org.thymeleaf.spring5.SpringTemplateEngine;
import org.thymeleaf.templateresolver.ClassLoaderTemplateResolver;
import org.thymeleaf.templateresolver.FileTemplateResolver;

import javax.servlet.http.HttpServletResponse;
import java.io.File;
import java.io.OutputStream;
import java.util.Map;

public class PdfUtil {

    /**
     * @param response     http请求后的相应
     * @param pdfFileName  pdf文件名称(不包含pdf后缀)
     * @param templateName 模板名称
     * @param variables    模板变量
     */
    public static void exportPdf(HttpServletResponse response, String pdfFileName, String templateName, Map<String, Object> variables) throws Exception {
        response.setContentType("application/pdf");
        response.setHeader("Content-Disposition", "attachment;filename=" + new String((pdfFileName + ".pdf").getBytes(), "iso8859-1"));
        OutputStream os = response.getOutputStream();
        //构造模板引擎
        ClassLoaderTemplateResolver resolver = new ClassLoaderTemplateResolver();
        resolver.setPrefix("pdf/templates/"); //模板所在目录，相对于当前classloader的classpath。
        resolver.setSuffix(".html"); //模板文件后缀
//        FileTemplateResolver resolver = new FileTemplateResolver();
//        resolver.setPrefix(ServletActionContext.getServletContext().getRealPath("pdf/templates") + File.separator); // 如果放在web下
//        resolver.setSuffix(".html");

        SpringTemplateEngine templateEngine = new SpringTemplateEngine();
        templateEngine.setTemplateResolver(resolver);
        //构造上下文(Model)
        Context context = new Context();
        context.setVariable("pdfFileName", pdfFileName);
        context.setVariables(variables);
        //渲染模板
        String example = templateEngine.process(templateName, context);
        PdfRendererBuilder builder = new PdfRendererBuilder();
        //设置字体文件
        builder.useFont(ResourceUtils.getFile("classpath:pdf/fonts/SIMHEI.TTF"), "stxihei");
//        builder.useFont(new File(ServletActionContext.getServletContext().getRealPath("/pdf/fonts/SIMHEI.TTF")), "stxihei"); // 如果是放在web下面
        builder.useFastMode();
        builder.withHtmlContent(example, null);
        builder.toStream(os);
        builder.run();
    }
}

5、导出接口

 package com.libin.pdf.demo.controller;

import com.libin.pdf.demo.util.PdfUtil;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;

import javax.servlet.http.HttpServletResponse;
import java.util.HashMap;
import java.util.Map;

@RestController
public class DemoController {

    @GetMapping("pdf")
    public void test(HttpServletResponse response) throws Exception {
        Map<String, Object> variables = new HashMap<>();
        // 资源信息
        // 资源名称
        variables.put("resourceName", "XXXXXXXXXX");
        // 目录名称
        variables.put("infoName", "XXXXXXXXXX");
        //资源类型
        variables.put("resourceType", "XXXXXXXXXX");
        // 数据提供方
        variables.put("resOrgName", "XXXXXXXXXX");

        // 资源需求方
        variables.put("orgName", "XXXXXXXXXX");
        // 需求方系统
        variables.put("systemName", "XXXXXXXXXX");
        // 联系人
        variables.put("linkMan", "XXXXXXXXXX");
        // 联系手机
        variables.put("linkPhone", "XXXXXXXXXX");
        // 申请日期
        variables.put("orderDate", "XXXXXXXXXX");
        // 申请理由
        variables.put("orderReason", "XXXXXXXXXX");

        // 审核人
        variables.put("prejuUserName", "XXXXXXXXXX");
        // 审核结果
        variables.put("prejuResult", "XXXXXXXXXX");
        // 审核日期
        variables.put("prejuDate", "XXXXXXXXXX");
        // 审核意见
        variables.put("prejuSuggest", "XXXXXXXXXX");

        PdfUtil.exportPdf(response, "审批记录", "audit_order_record.html", variables);
    }
}