Converts a Path into a property
whose value is appropriate for a Manifest's
Class-Path attribute.
This task is often used to work around command line limitations on Windows when using very long class paths when launching an application. The long class path normally specified on the command line is replaced by a single (possibly empty) jar file which an in-manifest Class-Path attribute whose value lists all the jar and zip files the class path should contain. The files referenced from this attribute must be found relatively to the jar file itself, usually in the same directory. The Java VM automically uses all file entries listed in the Class-Path attributes of a jar to locate/load classes. Note though that it silently ignores entries for which it cannot find any corresponding file.
Note that the property value created may be longer than a manifest's maximum
72 characters per line, but will be properly wrapped as per the Jar
specification by the <manifest> element, where the
defined property is re-referenced.
For this task to work properly the relative path from the file
given in the jarfile attribute to the elements of the
nested classpath must be the same as you expect them to
be when deploying the jar.
since Apache Ant 1.7
| Attribute | Description | Required |
| property | the name of the property to set. This property must not already be set. | Yes |
| jarfile | the filename for the Jar which will contain the manifest that will use the property this task will set. This file need not exist yet, but its parent directory must exist. | Yes |
| maxParentLevels | The maximum number of parent directories one is allowed to traverse to navigate from the jar file to the path entry. Put differently, the maximum number of .. which is allowed in the relative path from the jar file to a given class path enty. Specify 0 to enforce a path entry to be in the same directory (or one of its sub-directories) as the jar file itself. Defaults to 2 levels. | No |
A Path-like element, which can be
defined in-place, or refer to a path defined elsewhere using the
<classpath refid="pathid" /> syntax.
This classpath must not be empty, and is required.
<manifestclasspath property="jar.classpath"
jarfile="build/acme.jar">
<classpath refid="classpath" />
</manifestclasspath>
Assuming a path of id "classpath" was already defined, convert this
path relatively to the build/ directory that will contain acme.jar, which
can later be created with <jar> with a nested
<manifest> element that lists an
<attribute name="Class-Path" value="${jar.classpath}" />.