如何在Java中提取tar文件?

2022-08-31 14:40:44

如何在Java中提取tar(或tar.gz或tar.bz2)文件?


答案 1

你可以使用Apache Commons Compress库来做到这一点。您可以从 http://mvnrepository.com/artifact/org.apache.commons/commons-compress/1.2 下载 1.2 版本。

这里有两种方法:一种用于解压缩文件,另一种用于解压缩文件。因此,对于文件<文件名>tar.gz,您需要先解压缩它,然后再解压缩它。请注意,tar 存档也可能包含文件夹,在这种情况下,需要在本地文件系统上创建它们。

享受。

/** Untar an input file into an output file.

 * The output file is created in the output folder, having the same name
 * as the input file, minus the '.tar' extension. 
 * 
 * @param inputFile     the input .tar file
 * @param outputDir     the output directory file. 
 * @throws IOException 
 * @throws FileNotFoundException
 *  
 * @return  The {@link List} of {@link File}s with the untared content.
 * @throws ArchiveException 
 */
private static List<File> unTar(final File inputFile, final File outputDir) throws FileNotFoundException, IOException, ArchiveException {

    LOG.info(String.format("Untaring %s to dir %s.", inputFile.getAbsolutePath(), outputDir.getAbsolutePath()));

    final List<File> untaredFiles = new LinkedList<File>();
    final InputStream is = new FileInputStream(inputFile); 
    final TarArchiveInputStream debInputStream = (TarArchiveInputStream) new ArchiveStreamFactory().createArchiveInputStream("tar", is);
    TarArchiveEntry entry = null; 
    while ((entry = (TarArchiveEntry)debInputStream.getNextEntry()) != null) {
        final File outputFile = new File(outputDir, entry.getName());
        if (entry.isDirectory()) {
            LOG.info(String.format("Attempting to write output directory %s.", outputFile.getAbsolutePath()));
            if (!outputFile.exists()) {
                LOG.info(String.format("Attempting to create output directory %s.", outputFile.getAbsolutePath()));
                if (!outputFile.mkdirs()) {
                    throw new IllegalStateException(String.format("Couldn't create directory %s.", outputFile.getAbsolutePath()));
                }
            }
        } else {
            LOG.info(String.format("Creating output file %s.", outputFile.getAbsolutePath()));
            final OutputStream outputFileStream = new FileOutputStream(outputFile); 
            IOUtils.copy(debInputStream, outputFileStream);
            outputFileStream.close();
        }
        untaredFiles.add(outputFile);
    }
    debInputStream.close(); 

    return untaredFiles;
}

/**
 * Ungzip an input file into an output file.
 * <p>
 * The output file is created in the output folder, having the same name
 * as the input file, minus the '.gz' extension. 
 * 
 * @param inputFile     the input .gz file
 * @param outputDir     the output directory file. 
 * @throws IOException 
 * @throws FileNotFoundException
 *  
 * @return  The {@File} with the ungzipped content.
 */
private static File unGzip(final File inputFile, final File outputDir) throws FileNotFoundException, IOException {

    LOG.info(String.format("Ungzipping %s to dir %s.", inputFile.getAbsolutePath(), outputDir.getAbsolutePath()));

    final File outputFile = new File(outputDir, inputFile.getName().substring(0, inputFile.getName().length() - 3));

    final GZIPInputStream in = new GZIPInputStream(new FileInputStream(inputFile));
    final FileOutputStream out = new FileOutputStream(outputFile);

    IOUtils.copy(in, out);

    in.close();
    out.close();

    return outputFile;
}

答案 2

注意:此功能后来通过一个单独的项目Apache Commons Compress发布,如另一个答案所述。这个答案已经过时了。


我没有直接使用tar API,但tar和bzip2是在Ant中实现的;你可以借用他们的实现,或者可能使用Ant来做你需要的事情。

Gzip是Java SE的一部分(我猜Ant实现遵循相同的模型)。

GZIPInputStream只是一个装饰者。例如,您可以将 a 包装在 a 中,并以与使用任何 :InputStreamFileInputStreamGZIPInputStreamInputStream

InputStream is = new GZIPInputStream(new FileInputStream(file));

(请注意,GZIPInputStream 有自己的内部缓冲区,因此将 包装在 中可能会降低性能。FileInputStreamBufferedInputStream


推荐