1.首先下载相关jar包和dll：https://sourceforge.net/projects/jacob-project/files/jacob-project/1.17/

jar包和dll工具

import java.io.File;

import com.jacob.activeX.ActiveXComponent;
import com.jacob.com.Dispatch;

public class Test {
    private static final int wdFormatPDF = 17;
    private static final int xlTypePDF = 0;
    private static final int ppSaveAsPDF = 32;

    public static void main(String[] args) {
        if (new Test().convert2PDF("C:/DS1-1-1.pptx","C:/DS1-1-1.pdf"))
            System.out.println("转换完成！");
        else
            System.out.println("转换失败!");
    }

    public boolean convert2PDF(String inputFile, String pdfFile) {
        String suffix = getFileSufix(inputFile);
        File file = new File(inputFile);
        if (!file.exists()) {
            return false;
        }
        if (suffix.equals("pdf")) {
            return false;
        }
        if (suffix.equals("ppt") || suffix.equals("pptx")) {
            System.out.println("begin:");
            return ppt2PDF(inputFile, pdfFile);
        }  else {
            return false;
        }
        return false;
    }

    public static String getFileSufix(String fileName) {
        int splitIndex = fileName.lastIndexOf(".");
        return fileName.substring(splitIndex + 1);
    }
    // ppt转换为pdf
    public static boolean ppt2PDF(String inputFile, String pdfFile) {
        try {
            ActiveXComponent app = new ActiveXComponent("KWPP.Application");
            // app.setProperty("Visible", msofalse);
            Dispatch ppts = app.getProperty("Presentations").toDispatch();

            Dispatch ppt = Dispatch.call(ppts, "Open", inputFile, true, // ReadOnly
                    true, // Untitled指定文件是否有标题
                    false// WithWindow指定文件是否可见
            ).toDispatch();

            Dispatch.call(ppt, "SaveAs", pdfFile, ppSaveAsPDF);

            Dispatch.call(ppt, "Close");

            app.invoke("Quit");
            return true;
        } catch (Exception e) {
            return false;
        }
    }
}