版权声明：本文为博主书香代码原创文章，未经博主允许不得转载。 https://blog.csdn.net/u010138825/article/details/80732786
使用这个库的初衷
找阿里编程规范的时候在github上搜索到的，觉得pdf像书籍一样的翻页比较自由，也是手痒吧。
启发开源项目github-pdf-demo
国人的EditMD比较不错我弄了一个MarkDown写作
页面是自己凑凑的看一下图：
pdf模板页面
<!DOCTYPE html>
<html>
<head lang="en">
<title>${title} - PDF</title>
<link href="http://localhost:8080/bootstrap/css/bootstrap.min.css" rel="stylesheet" type="text/css"/>
<link href="http://localhost:8080/css/pdfPage.css" rel="stylesheet" type="text/css"/>
<link href="http://localhost:8080/editormd/css/editormd.css" rel="stylesheet" type="text/css"/>
<style>
@page {
size: 210mm 297mm; /*设置纸张大小:A4(210mm 297mm)、A3(297mm 420mm) 横向则反过来*/
margin: 0.25in;
padding: 1em;
@bottom-center {
content: "Bamboo © 版权所有";
font-family: SimSun;
font-size: 12px;
color: #000;
};
@top-center {
content: element(header)
};
@bottom-right {
content: "第" counter(page) "页 共 " counter(pages) "页";
font-family: SimSun;
font-size: 12px;
color: #000;
};
}
</style>
</head>
<body style="font-family: SimSun;">
<div class="container">
<div class="projects-header page-header">
<h2 id="pdftitle" class="text-center" style=" width: 70%;">${title!获取标题失败}</h2>
<p id="pdflen" class="text-center" style=" width: 70%;">字数：${len!'0'}</p>
</div>
<div class="row" style="white-space:normal;word-wrap:break-word;word-break:break-all;width: 70%;">${content!'获取内容失败'}
</div>
</div>
</body>
</html>github项目工具类
package com.bamboo.markdown.paper.common;
import com.lowagie.text.DocumentException;
import com.lowagie.text.pdf.BaseFont;
import freemarker.template.Template;
import freemarker.template.TemplateException;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.util.CollectionUtils;
import org.springframework.web.servlet.view.freemarker.FreeMarkerConfigurer;
import org.w3c.dom.Document;
import org.xhtmlrenderer.pdf.ITextFontResolver;
import org.xhtmlrenderer.pdf.ITextRenderer;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletResponse;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import java.io.*;
import java.util.List;
import java.util.Map;
/**
* Created by admin on 2018/6/18.
* ftl模板转pdf处理工具类
*/
public class FtlTransPdfUtils {
private static final Logger LOGGER = LoggerFactory.getLogger(FtlTransPdfUtils.class);
/**
* 按模板和参数生成html字符串,再转换为flying-saucer识别的Document
*
* @param templateName freemarker模板名称
* @param variables freemarker模板参数
* @return Document
*/
private static Document generateDoc(FreeMarkerConfigurer configurer, String templateName, Map<String, Object> variables) {
Template tp;
try {
tp = configurer.getConfiguration().getTemplate(templateName);
} catch (IOException e) {
LOGGER.error(e.getMessage(), e);
return null;
}
StringWriter stringWriter = new StringWriter();
try (BufferedWriter writer = new BufferedWriter(stringWriter)) {
try {
tp.process(variables, writer);
writer.flush();
} catch (TemplateException e) {
LOGGER.error("模板不存在或者路径错误", e);
} catch (IOException e) {
LOGGER.error("IO异常", e);
}
DocumentBuilder builder = DocumentBuilderFactory.newInstance().newDocumentBuilder();
return builder.parse(new ByteArrayInputStream(stringWriter.toString().getBytes()));
} catch (Exception e) {
LOGGER.error(e.getMessage(), e);
return null;
}
}
/**
* 核心: 根据freemarker模板生成pdf文档
*
* @param configurer freemarker配置
* @param templateName freemarker模板名称
* @param out 输出流
* @param listVars freemarker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(FreeMarkerConfigurer configurer, String templateName, OutputStream out, List<Map<String, Object>> listVars) {
if (CollectionUtils.isEmpty(listVars)) {
LOGGER.warn("警告:freemarker模板参数为空!");
return;
}
ITextRenderer renderer = new ITextRenderer();
Document doc = generateDoc(configurer, templateName, listVars.get(0));
renderer.setDocument(doc, null);
//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();
try {
fontResolver.addFont("typeface/simsun.ttc", BaseFont.IDENTITY_H, BaseFont.NOT_EMBEDDED);
} catch (DocumentException e) {
LOGGER.error("S1DocumentException" + e.getMessage());
} catch (IOException e) {
LOGGER.error("S2IOException" + e.getMessage());
}
//展现和输出pdf
renderer.layout();
try {
renderer.createPDF(out, false);
} catch (DocumentException e) {
LOGGER.error("S3DocumentException" + e.getMessage());
}
//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 = 1; i < listVars.size(); i++) {
Document docAppend = generateDoc(configurer, templateName, listVars.get(i));
renderer.setDocument(docAppend, null);
renderer.layout();
try {
renderer.writeNextDocument(); //写下一个pdf页面
} catch (DocumentException e) {
LOGGER.error("S4DocumentException" + e.getMessage());
}
}
renderer.finishPDF(); //完成pdf写入
}
/**
* pdf下载
*
* @param configurer freemarker配置
* @param templateName freemarker模板名称(带后缀.ftl)
* @param listVars 模板参数集
* @param response HttpServletResponse
* @param fileName 下载文件名称(带文件扩展名后缀)
*/
public static void download(FreeMarkerConfigurer configurer, 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) {
LOGGER.error("X1" + e.getMessage());
}
try (ServletOutputStream out = response.getOutputStream()) {
generateAll(configurer, templateName, out, listVars);
out.flush();
} catch (Exception e) {
LOGGER.error("X2" + e.getMessage());
//X2java.io.IOException: 远程主机强迫关闭了一个现有的连接。
}
}
/**
* pdf预览
*
* @param configurer freemarker配置
* @param templateName freemarker模板名称(带后缀.ftl)
* @param listVars 模板参数集
* @param response HttpServletResponse
*/
public static void preview(FreeMarkerConfigurer configurer, String templateName, List<Map<String, Object>> listVars, HttpServletResponse response) {
try (ServletOutputStream out = response.getOutputStream()) {
generateAll(configurer, templateName, out, listVars);
out.flush();
} catch (Exception e) {
LOGGER.error(e.getMessage(), e);
}
}
}获取内容
package com.bamboo.markdown.paper.controller;
import com.bamboo.markdown.paper.common.FtlTransPdfUtils;
import com.bamboo.markdown.paper.entity.vo.ArticleView;
import com.bamboo.markdown.paper.repository.ArticleRepository;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.servlet.view.freemarker.FreeMarkerConfigurer;
import org.xml.sax.SAXException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
/**
* Created by admin on 2018/6/18.
*/
@Controller
@RequestMapping(value = "/pdf")
public class PdfController {
@Autowired
private FreeMarkerConfigurer configurer;
@Autowired
private ArticleRepository articleRepository;
/**
* pdf预览
*
* @param request HttpServletRequest
* @param response HttpServletResponse
*/
@RequestMapping(value = "/preview/{id}", method = RequestMethod.GET)
public void preview(HttpServletRequest request, HttpServletResponse response, @PathVariable Integer id) throws IOException, SAXException {
ArticleView articleView = new ArticleView(articleRepository.findById(id));
// 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<>();
variables.put("title", articleView.getTitle());
//补充修正
String htmlContent = articleView.getHtmlMaterial().replace("<br>", "<br/>");
//匹配img标签的正则表达式
String regxpForImgTag = "<img\\s[^>]+>";
Pattern pattern = Pattern.compile(regxpForImgTag);
Matcher matcher = pattern.matcher(htmlContent);
StringBuffer sbr = new StringBuffer();
while (matcher.find()) {
String temp = matcher.group();
matcher.appendReplacement(sbr, temp.replace(">", " />"));
}
matcher.appendTail(sbr);
String htmlMaterial = sbr.toString();
////
String regxpForImgTag2 = "<pre><code\\s[^>]+>";
Pattern pattern2 = Pattern.compile(regxpForImgTag2);
Matcher matcher2 = pattern2.matcher(htmlMaterial);
StringBuffer sbr2 = new StringBuffer();
while (matcher2.find()) {
String temp2 = matcher2.group();
matcher2.appendReplacement(sbr2, temp2.replace(
"<pre><code class=\"lang-java\">",
" <pre class=\"prettyprint linenums prettyprinted\" style=\"\"><code class=\"lang-java\">"));
}
matcher2.appendTail(sbr2);
variables.put("content", sbr2.toString());
variables.put("len", htmlMaterial.length());
listVars.add(variables);
//
FtlTransPdfUtils.preview(configurer, "pdf/pdfPage.ftl", listVars, response);
}
/**
* pdf下载
*
* @param request HttpServletRequest
* @param response HttpServletResponse
*/
@RequestMapping(value = "/download/{id}", method = RequestMethod.GET)
public void download(HttpServletRequest request, HttpServletResponse response, @PathVariable Integer id) {
ArticleView articleView = new ArticleView(articleRepository.findById(id));
List<Map<String, Object>> listVars = new ArrayList<>();
Map<String, Object> variables = new HashMap<>();
variables.put("title", articleView.getTitle());
//补充修正
String htmlContent = articleView.getHtmlMaterial().replace("<br>", "<br/>");
//匹配img标签的正则表达式
String regxpForImgTag = "<img\\s[^>]+>";
Pattern pattern = Pattern.compile(regxpForImgTag);
Matcher matcher = pattern.matcher(htmlContent);
StringBuffer sbr = new StringBuffer();
while (matcher.find()) {
String temp = matcher.group();
matcher.appendReplacement(sbr, temp.replace(">", " />"));
}
matcher.appendTail(sbr);
String htmlMaterial = sbr.toString();
////
String regxpForImgTag2 = "<pre><code\\s[^>]+>";
Pattern pattern2 = Pattern.compile(regxpForImgTag2);
Matcher matcher2 = pattern2.matcher(htmlMaterial);
StringBuffer sbr2 = new StringBuffer();
while (matcher2.find()) {
String temp2 = matcher2.group();
matcher2.appendReplacement(sbr2, temp2.replace(
"<pre><code class=\"lang-java\">",
" <pre class=\"prettyprint linenums prettyprinted\" style=\"\"><code class=\"lang-java\">"));
}
matcher2.appendTail(sbr2);
variables.put("content", sbr2.toString());
variables.put("len", htmlMaterial.length());
listVars.add(variables);
FtlTransPdfUtils.download(configurer, "pdf/pdfPage.ftl", listVars, response, articleView.getTitle() + ".pdf");
}
}
