NAME¶
Tree::Simple::Visitor::FindByUID - A Visitor for finding an element in a
Tree::Simple hierarchy by UID
SYNOPSIS¶
use Tree::Simple::Visitor::FindByUID;
# create a visitor object
my $visitor = Tree::Simple::Visitor::FindByUID->new();
# set the search path for our tree
$visitor->searchForUID("MyTreeUID");
# pass the visitor to a tree
$tree->accept($visitor);
# fetch the result, which will
# be the Tree::Simple object that
# we have found, or undefined
my $result = $visitor->getResult() || die "No Tree found";
DESCRIPTION¶
Given a UID and Tree::Simple hierarchy, this Visitor will attempt to find the
node with the same UID.
METHODS¶
- new
- There are no arguments to the constructor the object will
be in its default state. You can use the "setNodeFilter",
"setTraversalMethod", "includeTrunk" and
"searchForUID" methods to customize its behavior.
- includeTrunk ($boolean)
- Based upon the value of $boolean, this will tell the
visitor to include the trunk of the tree in the search as well.
- setTraversalMethod ($visitor)
- By default we will use Tree::Simple's built in depth-first
(pre-order) traverse method. If however, you desire the tree to be search
in a different ordering, this can be accomplished using a different
traversal method, you can supply a $visitor object implementing that
traversal type to this method (See
Tree::Simple::Visitor::BreadthFirstTraversal,
Tree::Simple::Visitor::PreOrderTraversal and
Tree::Simple::Visitor::PostOrderTraversal).
- searchForUID ($UID)
- This is the UID we will attempt to find within the
tree.
- setNodeFilter ($filter_function)
- This method accepts a CODE reference as its
$filter_function argument and throws an exception if it is not a code
reference. This code reference is used to further check the tree nodes as
they are searched and so can be used to customize search behavior. For
instance, you could to check against the UID as well as some other
criteria. The filter function should accept a single argument, which is
the current Tree::Simple object and return either true (1) on success, or
false (0) on failure.
- visit ($tree)
- This is the method that is used by Tree::Simple's
"accept" method. It can also be used on its own, it requires the
$tree argument to be a Tree::Simple object (or derived from a Tree::Simple
object), and will throw and exception otherwise.
- getResult
- This method will return the tree found with the specified
UID (set by the "searchForUID" method) or "undef" if
no tree is found.
BUGS¶
None that I am aware of. Of course, if you find a bug, let me know, and I will
be sure to fix it.
CODE COVERAGE¶
See the
CODE COVERAGE section in Tree::Simple::VisitorFactory for more
inforamtion.
SEE ALSO¶
These Visitor classes are all subclasses of
Tree::Simple::Visitor, which
can be found in the
Tree::Simple module, you should refer to that
module for more information.
ACKNOWLEDGEMENTS¶
- Thanks to Vitor Mori for the idea for this Visitor.
AUTHOR¶
stevan little, <stevan@iinteractive.com>
COPYRIGHT AND LICENSE¶
Copyright 2004, 2005 by Infinity Interactive, Inc.
<
http://www.iinteractive.com>
This library is free software; you can redistribute it and/or modify it under
the same terms as Perl itself.