public class PruningVisitor extends NodeVisitor
Constructor and Description |
---|
PruningVisitor(Lang lang) |
Modifier and Type | Method and Description |
---|---|
Node |
override(Node parent,
Node n)
Given a tree rooted at
n , the visitor has the option of
overriding all traversal of the children of n . |
public PruningVisitor(Lang lang)
public Node override(Node parent, Node n)
NodeVisitor
n
, the visitor has the option of
overriding all traversal of the children of n
. If no
changes were made to n
and the visitor wishes to prevent
further traversal of the tree, then it should return n
. If
changes were made to the subtree, then the visitor should return a
copy of n
with appropriate changes. Finally, if the
visitor does not wish to override traversal of the subtree rooted at
n
, then it should return null
.
The default implementation of this method is to call
override(n)
, as most subclasses do not need to know
the parent of the node n
.
override
in class NodeVisitor
parent
- The parent of n
,
null
if n
has no parent.n
- The root of the subtree to be traversed.null
if it
is to continue.