Apache POI 是用Java编写的免费开源的跨平台的 Java API，Apache POI提供API给Java程式对Microsoft Office格式档案读和写的功能。
POI 操作office需要的jar包：
<properties>
<poi.version>3.17</poi.version>
</properties>
<!-- poi office -->
<dependency>
<groupId>org.apache.poi</groupId>
<artifactId>poi</artifactId>
<version>${poi.version}</version>
</dependency>
<dependency>
<groupId>org.apache.poi</groupId>
<artifactId>poi-examples</artifactId>
<version>${poi.version}</version>
</dependency>
<dependency>
<groupId>org.apache.poi</groupId>
<artifactId>poi-ooxml</artifactId>
<version>${poi.version}</version>
</dependency>
<dependency>
<groupId>org.apache.poi</groupId>
<artifactId>poi-ooxml-schemas</artifactId>
<version>${poi.version}</version>
</dependency>
<dependency>
<groupId>org.apache.poi</groupId>
<artifactId>poi-scratchpad</artifactId>
<version>${poi.version}</version>
</dependency>
poi生成的原图清晰度比较有限，所以转高清图的思路是生成图片的时候放大图片。下面是代码的实现。
package com.gorun.platform.art.common.minio.http;
import javax.imageio.ImageIO;
import java.awt.*;
import java.awt.geom.Rectangle2D;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.util.ArrayList;
import java.util.List;
import java.util.UUID;
import org.apache.poi.xslf.usermodel.XMLSlideShow;
import org.apache.poi.xslf.usermodel.XSLFShape;
import org.apache.poi.xslf.usermodel.XSLFSlide;
import org.apache.poi.xslf.usermodel.XSLFTextParagraph;
import org.apache.poi.xslf.usermodel.XSLFTextRun;
import org.apache.poi.xslf.usermodel.XSLFTextShape;
public class Ppt {
public static void main(String[] args) {
File ppt = new File("C:\\Users\\lenovo\\Desktop\\7787.pptx");
String img = "C:\\Users\\lenovo\\Desktop\\demo";
System.out.println(converPPTtoImage(ppt,img,"png",8));
}
/**
* 将PPT 文件转换成image
*
* @param orignalPPTFile //PPT文件对象 如：d:/demo/demo1.ppt
* @param targetImageFileDir //转换后的图片保存路径 如：d:/demo/pptImg
* @param imageFormatNameString //图片转化的格式字符串 ，如："jpg"、"jpeg"、"bmp" "png" "gif" "tiff"
* @param times //生成图片放大的倍数,倍数越高，清晰度越高
* @return 图片名列表
*/
public static int converPPTtoImage(File orignalPPTFile,String targetImageFileDir,
String imageFormatNameString, int times) {
//验证图片是否为pptx格式
if(!checkIsPPTFile(orignalPPTFile)){
System.out.print("转换文件必须是pptx!");
return 0;
}
List<String> list = new ArrayList<String>();
FileInputStream is = null ;
int imgCount = 0;
File imgFile = new File(targetImageFileDir);
//如果没有文件夹就创建文件夹
createDirIfNotExist(targetImageFileDir);
try {
is = new FileInputStream(orignalPPTFile);
XMLSlideShow xmlSlideShow = new XMLSlideShow(is);
is.close();
// 获取大小
Dimension pgsize = xmlSlideShow.getPageSize();
// 获取幻灯片
XSLFSlide[] slides = xmlSlideShow.getSlides().toArray(new XSLFSlide[0]);
imgCount = slides.length;
for (int i = 0 ; i < slides.length ; i++) {
// 解决乱码问题
XSLFShape[] shapes = slides[i].getShapes().toArray(new XSLFShape[0]);
for (XSLFShape shape : shapes) {
if (shape instanceof XSLFTextShape) {
XSLFTextShape sh = (XSLFTextShape) shape;
List<XSLFTextParagraph> textParagraphs = sh.getTextParagraphs();
for (XSLFTextParagraph xslfTextParagraph : textParagraphs) {
List<XSLFTextRun> textRuns = xslfTextParagraph.getTextRuns();
for (XSLFTextRun xslfTextRun : textRuns) {
xslfTextRun.setFontFamily("宋体");
}
}
}
}
// 创建BufferedImage对象，图像的尺寸为原来的每页的尺寸*倍数times
BufferedImage img = new BufferedImage(pgsize.width * times,
pgsize.height * times, BufferedImage.TYPE_INT_RGB);
Graphics2D graphics = img.createGraphics();
graphics.setPaint(Color.white);
graphics.scale(times, times);// 将图片放大times倍
graphics.fill(new Rectangle2D.Float(0, 0, pgsize.width,pgsize.height));
// 最核心的代码
slides[i].draw(graphics);
//图片将要存放的路径
String absolutePath = imgFile.getAbsolutePath()+"/"+ (i + 1)
+ "_" + UUID.randomUUID().toString() + "." + imageFormatNameString;
File jpegFile = new File(absolutePath);
// 图片路径存放
list.add((i + 1) + ".jpg");
//如果图片存在，则不再生成
if (jpegFile.exists()) {
continue;
}
// 这里设置图片的存放路径和图片的格式(jpeg,png,bmp等等),注意生成文件路径
FileOutputStream out = new FileOutputStream(jpegFile);
// 写入到图片中去
ImageIO.write(img, "jpeg", out);
out.close();
}
System.out.print("PPT转换成图片 成功！");
return imgCount;
}
catch (Exception e) {
e.printStackTrace();
System.out.print("PPT转换成图片 发生异常！");
}
return imgCount;
}
/**
* 检查是否为ppt文件
* @param file
* @return
*/
public static boolean checkIsPPTFile(File file) {
boolean isppt = false;
String filename = file.getName();
String suffixname = null;
if (filename != null && filename.indexOf(".") != -1) {
suffixname = filename.substring(filename.lastIndexOf("."));
if (".pptx".equals(suffixname)) {
isppt = true;
}
return isppt;
} else {
return isppt;
}
}
/**
* 创建文件如果路径不存在则创建对应的文件夹
* @param file
* @return
*/
public static File createDirIfNotExist(String file) {
File fileDir = new File(file);
if (!fileDir.exists()) {
fileDir.mkdirs();
}
return fileDir;
}
}