本文是将PDF文档转PNG图片,然后进行图片拼接,拼接后的图片转为base64字符串,然后拼接html文档(再写入html文件)。
引入maven依赖
xml
<!-- https://mvnrepository.com/artifact/org.apache.pdfbox/pdfbox -->
<dependency>
<groupId>org.apache.pdfbox</groupId>
<artifactId>pdfbox</artifactId>
<version>2.0.12</version>
</dependency>
工具实现类
java
package cn.yueworld.pms.web.util;
import cn.yueworld.framework.tools.exception.LogicException;
import org.apache.pdfbox.pdmodel.PDDocument;
import org.apache.pdfbox.rendering.PDFRenderer;
import org.jsoup.Jsoup;
import org.jsoup.nodes.Document;
import org.jsoup.nodes.Element;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import sun.misc.BASE64Encoder;
import javax.imageio.ImageIO;
import java.awt.*;
import java.awt.image.BufferedImage;
import java.io.*;
import java.net.URL;
/**
* PDF文档转HTML文档
*
* @author zkg
* @since 2024/6/11 16:45
*/
public class PdfConvertHtmlUtil {
/**
* 日志对象
*/
private static Logger logger = LoggerFactory.getLogger(PdfConvertHtmlUtil.class);
/**
* pdf转图片
*
* @param pdfUrl pdf路径
* @return BufferedImage 图片
*/
public static BufferedImage pdfToImage(String pdfUrl) {
PDDocument doc = null;
try {
// 本地文件
// File file = new File("C:\\Users\\Dell\\Downloads\\测试.pdf");
// inputStream = new FileInputStream(file);
logger.info("解析pdf+pdfUrl:" + pdfUrl);
URL url = new URL(pdfUrl);
InputStream inputStream = url.openStream();
doc = PDDocument.load(inputStream);
PDFRenderer renderer = new PDFRenderer(doc);
int pageCount = doc.getNumberOfPages();
BufferedImage image = null;
for (int i = 0; i < pageCount; i++) {
if (image != null) {
image = combineBufferedImages(image, renderer.renderImageWithDPI(i, 144));
}
if (i == 0) {
image = renderer.renderImageWithDPI(i, 144); // Windows native DPI
}
// BufferedImage srcImage = resize(image, 240, 240);//产生缩略图
}
return combineBufferedImages(image);
} catch (IOException e) {
e.printStackTrace();
} finally {
try {
if (doc != null) {
doc.close();
}
} catch (IOException e) {
e.printStackTrace();
}
}
return null;
}
/**
* BufferedImage拼接处理,添加分割线
*
* @param images 文件
* @return BufferedImage 添加分割线
*/
public static BufferedImage combineBufferedImages(BufferedImage... images) {
int height = 0;
int width = 0;
for (BufferedImage image : images) {
//height += Math.max(height, image.getHeight());
height += image.getHeight();
width = image.getWidth();
}
BufferedImage combo = new BufferedImage(width, height, BufferedImage.TYPE_INT_ARGB);
Graphics2D g2 = combo.createGraphics();
int x = 0;
int y = 0;
for (BufferedImage image : images) {
//int y = (height - image.getHeight()) / 2;
g2.setStroke(new BasicStroke(2.0f));// 线条粗细
g2.setColor(new Color(193, 193, 193));// 线条颜色
g2.drawLine(x, y, width, y);// 线条起点及终点位置
g2.drawImage(image, x, y, null);
//x += image.getWidth();
y += image.getHeight();
}
return combo;
}
/**
* 通过Base64创建HTML文件并输出html文件
*
* @param base64 文件的base64
* @param htmlUrl html保存路径
*/
public static void createHtmlByBase64(String base64, String htmlUrl) {
StringBuilder stringHtml = new StringBuilder();
PrintStream printStream = null;
try {
// 打开文件
printStream = new PrintStream(new FileOutputStream(htmlUrl));
} catch (FileNotFoundException e) {
e.printStackTrace();
}
// 输入HTML文件内容
stringHtml.append("<html><head>");
stringHtml.append("<meta http-equiv=\"Content-Type\" content=\"text/html; charset=UTF-8\">");
stringHtml.append("<title></title>");
stringHtml.append("</head>");
stringHtml.append("<body style=\"\r\n" + " text-align: center;\r\n" + " background-color: #C1C1C1;\r\n" + "\">");
stringHtml.append("<img src=\"data:image/png;base64," + base64 + "\" />");
stringHtml.append("<a name=\"head\" style=\"position:absolute;top:0px;\"></a>");
//添加锚点用于返回首页
stringHtml.append("<a style=\"position:fixed;bottom:10px;right:10px\" href=\"#head\">回到首页</a>");
stringHtml.append("</body></html>");
try {
// 将HTML文件内容写入文件中
printStream.println(stringHtml.toString());
} catch (Exception e) {
e.printStackTrace();
} finally {
if (printStream != null) {
printStream.close();
}
}
}
/**
* 图片转为base64编码
*
* @param bufferedImage 图片
* @return base64编码
*/
public static String bufferedImageToBase64(BufferedImage bufferedImage) {
ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();
String png_base64 = "";
try {
ImageIO.write(bufferedImage, "png", byteArrayOutputStream);// 写入流中
byte[] bytes = byteArrayOutputStream.toByteArray();// 转换成字节
BASE64Encoder encoder = new BASE64Encoder();
// 转换成base64串 删除 \r\n
png_base64 = encoder.encodeBuffer(bytes).trim()
.replaceAll("\n", "")
.replaceAll("\r", "");
} catch (IOException e) {
e.printStackTrace();
}
return png_base64;
}
/**
* 将图片的base64编码替换到html文件里面
*
* @param htmlUrl 文件路径
* @param base64 图片
* @return html
*/
public static Document htmlReplaceTag(String htmlUrl, String base64) {
try {
// 读取文件
// File file = new File(htmlUrl);
// Document document = Jsoup.parse(file, "UTF-8");
logger.info("解析html+htmlUrl" + htmlUrl);
// 使用Jsoup.connect方法获取Document对象
Document document = Jsoup.connect(htmlUrl).get();
logger.info("替换元素内容开始:" + document);
// 通过ID获取要替换的元素
Element oldTag = document.getElementById("pdfFileId");
if (oldTag != null) {
// 替换元素内容
if (base64 != null) {
// 创建新标签
Element newTag = document.createElement("img");
// 设置图片的id
newTag.attr("id", "pdfFileId");
// 设置图片的属性
newTag.attr("src", "data:image/png;base64," + base64);
// 替换旧标签
oldTag.replaceWith(newTag);
} else {
oldTag.remove();
}
logger.info("替换元素内容结束:" + document);
}
// 保存修改后的HTML文件
document.outputSettings().charset("UTF-8");
document.outputSettings().prettyPrint(true);
// 写到本地
// FileWriter fileWriter = new FileWriter(new File("C:\\Users\\Dell\\Downloads\\测试.html"));
// fileWriter.write(document.outerHtml());
// fileWriter.close();
return document;
} catch (Exception e) {
e.printStackTrace();
logger.error("将图片的base64编码替换到html文件里面失败:" + e.getMessage());
throw new LogicException("将图片的base64编码替换到html文件里面失败");
}
}
/**
* html + pdf
*
* @param htmlUrl 文件路径
* @param pdfUrl 图片
* @return html
*/
public static Document htmlAddPdf(String htmlUrl, String pdfUrl) {
try {
String base64_png = null;
if (pdfUrl != null) {
// pdf转图片
BufferedImage bufferedImage = pdfToImage(pdfUrl);
// 图片转为base64编码
base64_png = bufferedImageToBase64(bufferedImage);
}
// 将图片的base64编码替换到html文件里面
return htmlReplaceTag(htmlUrl, base64_png);
} catch (Exception e) {
e.printStackTrace();
logger.error("pdf文件转换失败:" + e.getMessage());
throw new LogicException("pdf文件转换失败:" + e.getMessage());
}
}
}
测试Demo
java
public static void main(String[] args) {
// PDF文件URL
String pdfUrl = "https://geli-dev.yueworld.cn:8060/group1/M00/00/47/wKh5GWZfvn6AILBZAASNWOGlbkI479.pdf";
// HTML文件路径
String htmlUrl = "https://geli-dev.yueworld.cn:8060/cm_web/print/cm_Zlcontract001/#/cm_Zlcontract001?conId=2371";
Document document = htmlAddPdf(htmlUrl, pdfUrl);
System.out.println("结果:" + document);
}
可以是在线的pfd、html,也可以是本地的pdf和html,两种方法工具类里面都有。
第三方库Jsoup
其中在线的html需要使用第三方库Jsoup,Jsoup是一个开源的Java库,它提供了简单和方便的API来处理HTML文档。
你可以使用以下代码添加Jsoup依赖项到你的项目中:
依赖
java
<dependency>
<groupId>org.jsoup</groupId>
<artifactId>jsoup</artifactId>
<version>1.13.1</version>
</dependency>
下面是一个使用Jsoup获取网页HTML数据的示例代码:
java
import org.jsoup.Jsoup;
import org.jsoup.nodes.Document;
public class HtmlFetcher {
public static void main(String[] args) {
try {
// 使用Jsoup.connect方法获取Document对象
Document doc= Jsoup.connect(htmlUrl).get();
String htmlData = doc.html();
System.out.println(htmlData);
} catch (Exception e) {
e.printStackTrace();
}
}
}