java - 读取 pdf 时 ScratchFileBuffer 未关闭消息

Question

我有这段代码可以从 pdf 中读取并提取字符串。

它运行良好，但是日志重复抛出此消息，我不知道为什么:

public class Test {
    public static void main(String[] args) {

        PDDocument doc = null;
        try {
            doc = PDDocument.load(new File("C:/prueba.pdf"));
            PDFTextStripper pdfs = new PDFTextStripper();
            String textOfPdf = "";

            textOfPdf = pdfs.getText(doc);
            String regex = "([A-Z0-9]{5}-[A-Z0-9]{5}-[A-Z0-9]{5}-[A-Z0-9]{5}-[A-Z0-9]{5}-[A-Z0-9]{5})";
            Pattern patron = Pattern.compile(regex);

            Matcher emparejador = patron.matcher(textOfPdf);
            emparejador.find();
            String text = emparejador.group(0);

            System.out.print(text);
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            try {
                if (doc != null) {
                    doc.close();
                }
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }
}

12:52:37.335 [main] DEBUG org.apache.pdfbox.pdfparser.PDFObjectStreamParser - parsed=COSObject{25, 0}
12:52:37.336 [main] DEBUG org.apache.pdfbox.pdfparser.PDFObjectStreamParser - parsed=COSObject{26, 0}
12:52:37.336 [main] DEBUG org.apache.pdfbox.pdfparser.PDFObjectStreamParser - parsed=COSObject{28, 0}
12:52:37.336 [main] DEBUG org.apache.pdfbox.pdfparser.PDFObjectStreamParser - parsed=COSObject{27, 0}
12:52:37.336 [main] DEBUG org.apache.pdfbox.pdfparser.PDFObjectStreamParser - parsed=COSObject{30, 0}
12:52:37.337 [main] DEBUG org.apache.pdfbox.pdfparser.PDFObjectStreamParser - parsed=COSObject{31, 0}
12:52:37.338 [main] DEBUG org.apache.pdfbox.pdfparser.PDFObjectStreamParser - parsed=COSObject{5, 0}

12:52:37.772 [Finalizer] DEBUG org.apache.pdfbox.io.ScratchFileBuffer - ScratchFileBuffer not closed!
12:52:37.772 [Finalizer] DEBUG org.apache.pdfbox.io.ScratchFileBuffer - ScratchFileBuffer not closed!
12:52:37.772 [Finalizer] DEBUG org.apache.pdfbox.io.ScratchFileBuffer - ScratchFileBuffer not closed!
12:52:37.773 [Finalizer] DEBUG org.apache.pdfbox.io.ScratchFileBuffer - ScratchFileBuffer not closed!
12:52:37.773 [Finalizer] DEBUG org.apache.pdfbox.io.ScratchFileBuffer - ScratchFileBuffer not closed!
12:52:37.773 [Finalizer] DEBUG org.apache.pdfbox.io.ScratchFileBuffer - ScratchFileBuffer not closed!
12:52:37.773 [Finalizer] DEBUG org.apache.pdfbox.io.ScratchFileBuffer - ScratchFileBuffer not closed!
12:52:37.773 [Finalizer] DEBUG org.apache.pdfbox.io.ScratchFileBuffer - ScratchFileBuffer not closed!
12:52:37.773 [Finalizer] DEBUG org.apache.pdfbox.io.ScratchFileBuffer - ScratchFileBuffer not closed!

我也尝试过 tess4j 库，但发生了同样的事情。有什么想法吗？

问候

Answer 1

这很可能是内部解析器问题。从表面上看，某些 PDF 对象没有显式关闭它们使用的临时文件，而是在 Finalize 方法中关闭。

对我来说这似乎不是问题，除了关闭该类的调试级别日志记录之外，您无能为力。

log4j.logger.org.apache.pdfbox.io.ScratchFileBuffer=WARN