polyglot.visit
Class HandoffVisitor

java.lang.Object
  extended by polyglot.visit.NodeVisitor
      extended by polyglot.visit.HandoffVisitor
All Implemented Interfaces:
java.lang.Cloneable, Copy

public class HandoffVisitor
extends NodeVisitor

This visitor adds jobs for SourceFiles in the AST to the schedule of another extension.


Field Summary
protected  ExtensionInfo ext
           
 
Constructor Summary
HandoffVisitor(ExtensionInfo ext)
           
 
Method Summary
 Node leave(Node old, Node n, NodeVisitor v)
          This method is called after all of the children of n have been visited.
 Node override(Node n)
          Given a tree rooted at n, the visitor has the option of overriding all traversal of the children of n.
 
Methods inherited from class polyglot.visit.NodeVisitor
begin, copy, enter, enter, finish, finish, leave, override, toString, visitEdge, visitEdgeNoOverride
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait
 

Field Detail

ext

protected ExtensionInfo ext
Constructor Detail

HandoffVisitor

public HandoffVisitor(ExtensionInfo ext)
Method Detail

override

public Node override(Node n)
Description copied from class: NodeVisitor
Given a tree rooted at 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.

This method is typically called by the method override(parent, n). If a subclass overrides the method override(parent, n) then this method may not be called.

Overrides:
override in class NodeVisitor
Parameters:
n - The root of the subtree to be traversed.
Returns:
A node if normal traversal is to stop, null if it is to continue.

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.