How to Compress/Decompress tar.gz files in java

Question

Can anyone show me the correct way to compress and decompress tar.gzip files in java i\'ve been searching but the most i can find is either zip or gzip(alone).

Answer 1

To extract the contents of .tar.gz format, I successfully use apache commons-compress ('org.apache.commons:commons-compress:1.12'). Take a look at this example method:

public void extractTarGZ(InputStream in) {
    GzipCompressorInputStream gzipIn = new GzipCompressorInputStream(in);
    try (TarArchiveInputStream tarIn = new TarArchiveInputStream(gzipIn)) {
        TarArchiveEntry entry;

        while ((entry = (TarArchiveEntry) tarIn.getNextEntry()) != null) {
            /** If the entry is a directory, create the directory. **/
            if (entry.isDirectory()) {
                File f = new File(entry.getName());
                boolean created = f.mkdir();
                if (!created) {
                    System.out.printf("Unable to create directory '%s', during extraction of archive contents.\n",
                            f.getAbsolutePath());
                }
            } else {
                int count;
                byte data[] = new byte[BUFFER_SIZE];
                FileOutputStream fos = new FileOutputStream(entry.getName(), false);
                try (BufferedOutputStream dest = new BufferedOutputStream(fos, BUFFER_SIZE)) {
                    while ((count = tarIn.read(data, 0, BUFFER_SIZE)) != -1) {
                        dest.write(data, 0, count);
                    }
                }
            }
        }

        System.out.println("Untar completed successfully!");
    }
}

Answer 2

In my experience Apache Compress is much more mature than Plexus Archiver, specifically because of issues like http://jira.codehaus.org/browse/PLXCOMP-131.

I believe Apache Compress has more activity as well.

Answer 3

It works for me, using GZIPInputStream, https://www.mkyong.com/java/how-to-decompress-file-from-gzip-file/

Answer 4

I've written a wrapper for commons-compress called jarchivelib that makes it easy to extract or compress from and into File objects.

Example code would look like this:

File archive = new File("/home/thrau/archive.tar.gz");
File destination = new File("/home/thrau/archive/");

Archiver archiver = ArchiverFactory.createArchiver("tar", "gz");
archiver.extract(archive, destination);

Answer 5

If you are planning to compress/decompress on Linux, you can call the shell command line to do that for you:

Files.createDirectories(Paths.get(target));
ProcessBuilder builder = new ProcessBuilder();
builder.command("sh", "-c", String.format("tar xfz %s -C %s", tarGzPathLocation, target));
builder.directory(new File("/tmp"));
Process process = builder.start();
int exitCode = process.waitFor();
assert exitCode == 0;

Answer 6

My favorite is plexus-archiver - see sources on GitHub.

Another option is Apache commons-compress - (see mvnrepository).

With plexus-utils, the code for unarchiving looks like this:

final TarGZipUnArchiver ua = new TarGZipUnArchiver();
// Logging - as @Akom noted, logging is mandatory in newer versions, so you can use a code like this to configure it:
ConsoleLoggerManager manager = new ConsoleLoggerManager();
manager.initialize();
ua.enableLogging(manager.getLoggerForComponent("bla"));
// -- end of logging part
ua.setSourceFile(sourceFile);
destDir.mkdirs();
ua.setDestDirectory(destDir);
ua.extract();

Similar *Archiver classes are there for archiving.

With Maven, you can use this dependency:

<dependency>
  <groupId>org.codehaus.plexus</groupId>
  <artifactId>plexus-archiver</artifactId>
  <version>2.2</version>
</dependency>