Display the "Optional Package" and "Package Specification" information contained within the specified jars.

Note that this task works with extensions as defined by the "Optional Package" specification. For more information about optional packages, see the document Optional Package Versioning in the documentation bundle for your Java2 Standard Edition package, in file guide/extensions/versioning.html or online at

See the Extension and ExtensionSet documentation for further details


Attribute Description Required
file The file to display extension information about. No, but one of file or fileset must be present.

Parameters specified as nested elements


FileSets contain list of files to display Extension information about.


Display Extension info for a single file

  <jarlib-display file="myfile.jar">

Display Extension info for a fileset


    <fileset dir="lib">

      <include name="*.jar"/>



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