asponse，PPT转PDF空指针异常

问题遇到的现象和发生背景

我在使用asponse将PPT转成PDF时，提示我空指针异常

问题相关代码，请勿粘贴截图

public static void main(String[] args) throws IOException {
        String outPath = "D:/project/123.pdf";
        String inPath = "D:/project/22.pptx";
        if (!isPptLicense()) {
            return;
        }
        FileOutputStream outputStream = null;
        //读取ppt文件
        FileInputStream fileInput = new FileInputStream(inPath);
        System.out.println(fileInput.toString());
        Presentation pres = new Presentation(fileInput);
        //指定输出路径
        outputStream = new FileOutputStream(new File(outPath));
        //输出
        pres.save(outputStream, com.aspose.slides.SaveFormat.Pdf);
        outputStream.close();
    }

private static boolean isPptLicense() {
        boolean result = false;
        try {
            String license =
                    "<License>\n" +
                            "  <Data>\n" +
                            "    <Products>\n" +
                            "      <Product>Aspose.Total for Java</Product>\n" +
                            "      <Product>Aspose.Words for Java</Product>\n" +
                            "    </Products>\n" +
                            "    <EditionType>Enterprise</EditionType>\n" +
                            "    <SubscriptionExpiry>20991231</SubscriptionExpiry>\n" +
                            "    <LicenseExpiry>20991231</LicenseExpiry>\n" +
                            "    <SerialNumber>8bfe198c-7f0c-4ef8-8ff0-acc3237bf0d7</SerialNumber>\n" +
                            "  </Data>\n" +
                            "  <Signature>sNLLKGMUdF0r8O1kKilWAGdgfs2BvJb/2Xp8p5iuDVfZXmhppo+d0Ran1P9TKdjV4ABwAgKXxJ3jcQTqE/2IRfqwnPf8itN8aFZlV3TJPYeD3yWE7IT55Gz6EijUpC7aKeoohTb4w2fpox58wWoF3SNp6sK6jDfiAUGEHYJ9pjU=</Signature>\n" +
                            "</License>";
            InputStream is = new ByteArrayInputStream(license.getBytes("UTF-8"));
            com.aspose.slides.License aposeLic = new com.aspose.slides.License();
            aposeLic.setLicense(is);
            result = true;
        } catch (Exception e) {
            e.printStackTrace();
        }
        return result;
    }

运行结果及报错内容

我的解答思路和尝试过的方法

我最开始以为是我路径的问题，因此我尝试把路径改为D:\project\123.pdf，但是还是不行。同样的方法我去处理word和Excel转PDF都没问题，唯独PPT失败，我使用的slides版本是15.9.0

我想要达到的结果

[](链接：https://pan.baidu.com/s/1tP0SC4bxl39msg8zVqvMqg
提取码：x8tp)
这是我使用的jar包

这是官方的示例，直接另存即可，不用Stream

package com.aspose.slides.examples.presentations.conversion;

import com.aspose.slides.Presentation;
import com.aspose.slides.SaveFormat;
import com.aspose.slides.examples.RunExamples;


public class ConvertToPDF
{
    public static void main(String[] args)
    {
        //ExStart:ConvertToPDF
        // The path to the documents directory.
        String dataDir = RunExamples.getDataDir_Conversion();

        // Instantiate a Presentation object that represents a presentation file
        Presentation presentation = new Presentation(dataDir + "ConvertToPDF.pptx");
        try
        {
            // Save the presentation to PDF with default options
            presentation.save(dataDir + "output_out.pdf", SaveFormat.Pdf);
        }
        finally
        {
            if (presentation != null) presentation.dispose();
        }
        //ExEnd:ConvertToPDF            
    }
}

是不是路径有问题啊？检查一下

public bool PptToPdf(string PathFile, string OutPathFile)
{
try
{
//PPT
Presentation ppt = new Presentation(PathFile);
ppt.Save(OutPathFile, Aspose.Slides.Export.SaveFormat.Pdf);
return true;
}
catch (Exception ex)
{
return false;
}
}

检查方法是否适用于当前版本的 Aspose.Cells 和 Aspose.Slides for Java 的 ppt、pptx、xls 和 xlsx 文件，有的可能不适用于ppt文件。
（下面是一个在stackoverflow寻找到的一个相关解答，希望能帮助到你）
https://stackoverflow.com/questions/15762792/aspose-xlsx-and-pptx-files-conversion-exception