如何在Java中将InputStream转换为PDF，而不损坏文件？

import com.itextpdf.text.Document;
import com.itextpdf.text.DocumentException;
import com.itextpdf.text.Paragraph;
import com.itextpdf.text.pdf.PdfWriter;

import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;

public class InputStreamToPDF {

    public static void main(String[] args) {
        InputStream inputStream = ...; // 获取您的InputStream
        FileOutputStream outputStream = null;
        try {
            outputStream = new FileOutputStream("output.pdf");

            Document document = new Document();
            PdfWriter.getInstance(document, outputStream);
            document.open();

            // 假设InputStream包含纯文本
            byte[] buffer = new byte[1024];
            int bytesRead;
            StringBuilder sb = new StringBuilder();
            while ((bytesRead = inputStream.read(buffer)) != -1) {
                sb.append(new String(buffer, 0, bytesRead));
            }
            document.add(new Paragraph(sb.toString()));

            document.close();
        } catch (DocumentException | IOException e) {
            e.printStackTrace();
        } finally {
            if (outputStream != null) {
                try {
                    outputStream.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
            if (inputStream != null) {
                try {
                    inputStream.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
    }
}