polyglot.visit
Class DeadCodeEliminator.DefUseFinder
java.lang.Object
polyglot.visit.NodeVisitor
polyglot.visit.HaltingVisitor
polyglot.visit.DeadCodeEliminator.DefUseFinder
- All Implemented Interfaces:
- java.lang.Cloneable, Copy
- Enclosing class:
- DeadCodeEliminator
protected static class DeadCodeEliminator.DefUseFinder
- extends HaltingVisitor
Field Summary |
protected java.util.Set |
def
|
protected java.util.Set |
use
|
Methods inherited from class java.lang.Object |
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait |
def
protected java.util.Set def
use
protected java.util.Set use
DeadCodeEliminator.DefUseFinder
public DeadCodeEliminator.DefUseFinder(java.util.Set def,
java.util.Set use)
enter
public NodeVisitor enter(Node n)
- Description copied from class:
NodeVisitor
- Begin normal traversal of a subtree rooted at
n
. This gives
the visitor the option of changing internal state or returning a new
visitor which will be used to visit the children of n
.
This method is typically called by the method
enter(parent, n)
. If a subclass overrides the
method enter(parent, n)
then this method
may not be called.
- Overrides:
enter
in class NodeVisitor
- Parameters:
n
- The root of the subtree to be traversed.
- Returns:
- The
NodeVisitor
which should be used to visit the
children of n
.
leave
public Node leave(Node old,
Node n,
NodeVisitor v)
- Description copied from class:
NodeVisitor
- This method is called after all of the children of
n
have been visited. In this case, these children were visited by the
visitor v
. This is the last chance for the visitor to
modify the tree rooted at n
. This method will be called
exactly the same number of times as entry
is called.
That is, for each node that is not overriden, enter
and
leave
are each called exactly once.
Note that if old == n
then the vistior should make a copy
of n
before modifying it. It should then return the
modified copy.
This method is typically called by the method
leave(parent, old, n v)
.
If a subclass overrides the method
leave(parent, old, n v)
then this method may not be called.
- Overrides:
leave
in class NodeVisitor
- Parameters:
old
- The original state of root of the current subtree.n
- The current state of the root of the current subtree.v
- The NodeVisitor
object used to visit the children.
- Returns:
- The final result of the traversal of the tree rooted at
n
.