Exits the active build, giving an additional message if available. The
if and
unless attributes make the failure conditional -both probe for the named property being defined. The
if tests for the property being defined, the
unless for a property being undefined. If both attributes are set, then the test fails only if both tests are true. i.e.
fail := defined(ifProperty) && !defined(unlessProperty)
A single nested
<condition> element can be specified instead of using
if/
unless (a combined effect can be achieved using
isset conditions).
@since Ant 1.2
@ant.task name="fail" category="control"