Apache Commons Compress is a simple library that defines an API for working with ar, cpio, Unix dump, tar, zip, gzip, Pack200 and bzip2 files.
The compress component is split into compressors and archivers. While compressors (un)compress streams that usually store a single entry, archivers deal with archives that contain structured content represented by ArchiveEntry instances which in turn usually correspond to single files or directories.
Currently the bzip2, Pack200 and gzip formats are supported as compressors where gzip support is provided by the java.util.zip package
and Pack200 support by the java.util.jar package of the Java class library.