PDFBox文档到InputStream

Question

我正在尝试获取一个PDDocument对象并将其传递给其他模块,InputStream而不将文档保存到文件系统.

现在,我读到PDStream并且有点了解这个的目的.因此,我尝试做这样的事情:

PDStream stream = new PDStream(document);

InputStream is = stream.createInputStream();

但是当我尝试将输入流加载到a中时PDDocument,我收到此错误:

Exception in thread "main" java.io.IOException: Error: End-of-File, expected line
    at org.apache.pdfbox.pdfparser.BaseParser.readLine(BaseParser.java:1111)
    at org.apache.pdfbox.pdfparser.COSParser.parseHeader(COSParser.java:1885)
    at org.apache.pdfbox.pdfparser.COSParser.parsePDFHeader(COSParser.java:1868)
    at org.apache.pdfbox.pdfparser.PDFParser.parse(PDFParser.java:245)
    at org.apache.pdfbox.pdmodel.PDDocument.load(PDDocument.java:1098)
    at org.apache.pdfbox.pdmodel.PDDocument.load(PDDocument.java:995)
    at app.DGDCreator.main(DGDCreator.java:35)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:498)
    at com.intellij.rt.execution.application.AppMain.main(AppMain.java:143)

后来我发现结果文件大小为0kb ...

Answer 1

因此，其他任何人都可以对此找到一个很好的答案。我遇到了同样的情况，我不想将文件保存到任何计算机上，而只处理流本身。我在这里找到了答案，并将在下面重复。

ByteArrayOutputStream out = new ByteArrayOutputStream();
pdDoc.save(out);
pdDoc.close();
ByteArrayInputStream in = new ByteArrayInputStream(out.toByteArray());

Answer 2

我无法理解你为什么要这样做,但是,遵循代码将会这样做:

public static void main(String[] args) throws IOException {
    byte[] file = FileUtils.readFileToByteArray(new File(
            "C:\\temp\\a_file.pdf"));

    PDDocument document = null;

    InputStream is = null;
    ByteArrayOutputStream out = null;

    try {
        document = PDDocument.load(file);
        out = new ByteArrayOutputStream();

        document.save(out);

        byte[] data = out.toByteArray();
        is = new ByteArrayInputStream(data);

        FileUtils.writeByteArrayToFile(new File(
                "C:\\temp\\denemeTEST123.pdf"), IOUtils.toByteArray(is));
    } finally {
        IOUtils.closeQuietly(out);
        IOUtils.closeQuietly(is);
        IOUtils.closeQuietly(document);
    }
}