For each of the supported compression formats there is a correspondig task that uncompresses a resource. These tasks are based on their core cousin tasks.
If dest is a directory the name of the destination file is the same as src (with the compression specific extension removed if present). If dest is omitted, the parent dir of src is taken. The file is only expanded if the source resource is newer than the destination file, or when the destination file does not exist.
| Attribute | Description | Required |
| src | the file to expand. | Yes, or a nested resource collection. |
| dest | the destination file or directory. | No |
The specified resource will be used as src.
Is an uncompressing task that uses the BZIP2 compression algorithm.
Is an uncompressing task that uses the GZIP compression algorithm.
Is an uncompressing task that uses the Pack200 compression algorithm.
This task does not work on defalted archives, you need to wrap
defalted archives into gunzipresources in order to use
them.
In addition to the attributes supported by all uncompressing task this task also supports.
| Attribute | Description | Required |
| pack200strategy | Apache Commons Compress' Pack200 streams cache the archive data either in memory or in a temporary file. User this attribute to control which strategy is chosen. Valid values are "in-memory" and "temp-file". | No, defaults to in-memory. |
In addition to the nested elements supported by all uncompressing task this task also supports.
Sets a property for the unpacker (see the Pack200 javadocs for details).
| Attribute | Description | Required |
| key | Name of the property. | Yes. |
| value | Value of the property. | Yes. |
<cmp:gunzip src="test.tar.gz" xmlns:cmp="antlib:org.apache.ant.compress"/>
expands test.tar.gz to test.tar
<cmp:bunzip2 src="test.tar.bz2" xmlns:cmp="antlib:org.apache.ant.compress"/>
expands test.tar.bz2 to test.tar
<cmp:gunzip src="test.tar.gz" dest="test2.tar" xmlns:cmp="antlib:org.apache.ant.compress"/>
expands test.tar.gz to test2.tar
<cmp:gunzip src="test.tar.gz" dest="subdir" xmlns:cmp="antlib:org.apache.ant.compress"/>
expands test.tar.gz to subdir/test.tar (assuming subdir is a directory).
<cmp:gunzip dest="." xmlns:cmp="antlib:org.apache.ant.compress"> <url url="http://example.org/archive.tar.gz"/> </cmp:gunzip>
downloads http://example.org/archive.tar.gz and expands it to archive.tar in the project's basedir on the fly.
<cmp:unpack200 dest="foo.jar" xmlns:cmp="antlib:org.apache.ant.compress">
<cmp:gzipresource>
<file file="foo.pack.gz"/>
</cmp:gzipresource>
</cmp:unpack200>
Unpacks the deflated Pack200 archive foo.pack.gz and stores it as foo.jar.
<cmp:gunzip src="some-archive.gz" dest="some-dest-dir" xmlns:cmp="antlib:org.apache.ant.compress"/>is identical to
<copy todir="some-dest-dir">
<cmp:gzipresource xmlns:cmp="antlib:org.apache.ant.compress">
<file file="some-archive.gz"/>
</cmp:gzipresource>
<mapper type="glob" from="*.gz" to="*"/>
</copy>
The same is also true for <bunzip2> and
<bzip2resource>. <copy> offers
additional features like filtering
files on the fly,
allowing a file to be mapped to multiple destinations, preserving the
last modified time or a configurable file system timestamp
granularity.