用java实现office文件转pdf的程序

好的，以下是一个简单的Java程序示例，使用Apache POI和Apache PDFBox库将Office文件（Word、Excel和PowerPoint）转换为PDF文件：

import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import org.apache.poi.xwpf.usermodel.XWPFDocument;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;
import org.apache.poi.hslf.usermodel.HSLFSlideShow;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;
import org.apache.poi.openxml4j.exceptions.InvalidFormatException;
import org.apache.poi.ss.usermodel.Workbook;
import org.apache.poi.ss.usermodel.WorkbookFactory;
import org.apache.poi.xslf.usermodel.XMLSlideShow;
import org.apache.pdfbox.pdmodel.PDDocument;
import org.apache.pdfbox.pdmodel.PDPage;
import org.apache.pdfbox.pdmodel.PDPageContentStream;
import org.apache.pdfbox.pdmodel.font.PDType1Font;
import org.apache.pdfbox.pdmodel.graphics.image.LosslessFactory;
import org.apache.pdfbox.pdmodel.graphics.image.PDImageXObject;

public class OfficeToPDFConverter {

    public static void main(String[] args) throws IOException, InvalidFormatException {
        String inputFile = "input.docx";
        String outputFile = "output.pdf";
        convertToPdf(inputFile, outputFile);
    }

    public static void convertToPdf(String inputFile, String outputFile) throws IOException, InvalidFormatException {
        File inputFileObj = new File(inputFile);
        File outputFileObj = new File(outputFile);
        String fileExtension = getFileExtension(inputFileObj);

        if (fileExtension.equalsIgnoreCase("docx")) {
            XWPFDocument document = new XWPFDocument(WorkbookFactory.create(inputFileObj));
            PDDocument pdfDoc = new PDDocument();
            PDPage page = new PDPage();

            try (PDPageContentStream contentStream = new PDPageContentStream(pdfDoc, page)) {
                pdfDoc.addPage(page);
                contentStream.beginText();
                contentStream.setFont(PDType1Font.HELVETICA_BOLD, 12);
                contentStream.newLineAtOffset(20, 750);

                for (XWPFParagraph para : document.getParagraphs()) {
                    contentStream.showText(para.getText());
                    contentStream.newLine();
                }

                contentStream.endText();
            }

            pdfDoc.save(outputFileObj);
            pdfDoc.close();
            document.close();

        } else if (fileExtension.equalsIgnoreCase("xlsx")) {
            XSSFWorkbook workbook = new XSSFWorkbook(inputFileObj);
            PDDocument pdfDoc = new PDDocument();
            PDPage page = new PDPage();

            try (PDPageContentStream contentStream = new PDPageContentStream(pdfDoc, page)) {
                pdfDoc.addPage(page);
                contentStream.beginText();
                contentStream.setFont(PDType1Font.HELVETICA_BOLD, 12);
                contentStream.newLineAtOffset(20, 750);

                for (int i = 0; i < workbook.getNumberOfSheets(); i++) {
                    contentStream.showText(workbook.getSheetAt(i).getSheetName());
                    contentStream.newLine();
                }

                contentStream.endText();
            }

            pdfDoc.save(outputFileObj);
            pdfDoc.close();
            workbook.close();

        } else if (fileExtension.equalsIgnoreCase("pptx")) {
            XMLSlideShow ppt = new XMLSlideShow(WorkbookFactory.create(inputFileObj));
            PDDocument pdfDoc = new PDDocument();
            PDPage page = new PDPage();

            try (PDPageContentStream contentStream = new PDPageContentStream(pdfDoc, page)) {
                pdfDoc.addPage(page);
                contentStream.beginText();
                contentStream.setFont(PDType1Font.HELVETICA_BOLD, 12);
                contentStream.newLineAtOffset(20, 750);

                for (XSLFSlide slide : ppt.getSlides()) {
                    contentStream.showText(slide.getTitle());
                    contentStream.newLine();
                }

                contentStream.endText();
            }

            pdfDoc.save(outputFileObj);
            pdfDoc.close();
            ppt.close();

        } else if (fileExtension.equalsIgnoreCase("xls")) {
            HSSFWorkbook workbook = new HSSFWorkbook(inputFileObj);
            PDDocument pdfDoc = new PDDocument();
            PDPage page = new PDPage();

            try (PDPageContentStream contentStream = new PDPageContentStream(pdfDoc, page)) {
                pdfDoc.addPage(page);
                contentStream.beginText();
                contentStream.setFont(PDType1Font.HELVETICA_BOLD, 12);
                contentStream.newLineAtOffset(20, 750);

                for (int i = 0; i < workbook.getNumberOfSheets(); i++) {
                    contentStream.showText(workbook.getSheetAt(i).getSheetName());
                    contentStream.newLine();
                }

                contentStream.endText();
            }

            pdfDoc.save(outputFileObj);
            pdfDoc.close();
            workbook.close();
        }
    }

    private static String getFileExtension(File file) {
        String fileName = file.getName();
        if (fileName.lastIndexOf(".") != -1 && fileName.lastIndexOf(".") != 0) {
            return fileName.substring(fileName.lastIndexOf(".") + 1);
        } else {
            return "";
        }
    }
}

在此示例中，我们创建了一个名为`OfficeToPDFConverter`的Java类，该类使用Apache POI和Apache PDFBox库将Office文件（Word、Excel和PowerPoint）转换为PDF文件。在`main`方法中，我们调用`convertToPdf`方法，该方法接受输入文件路径和输出文件路径作为参数。在`convertToPdf`方法中，我们首先获取输入文件的扩展名，然后根据文件类型使用不同的POI库加载文件。然后，我们使用PDFBox库来创建一个PDF文档，并将Office文件的内容写入PDF页面。最后，我们将PDF文档保存到输出文件中。

请注意，在使用该程序之前，您需要下载并导入Apache POI和Apache PDFBox库。