com.interface21.core
Class PrettyPrintVisitor

java.lang.Object
  |
  +--com.interface21.core.PrettyPrintVisitor
All Implemented Interfaces:
Visitor

public class PrettyPrintVisitor
extends java.lang.Object
implements Visitor

Test visitor. Useful during development. Produces console output as it visits each node that shows the tree's structure.

Version:
1.0
Author:
Rod Johnson

Constructor Summary
PrettyPrintVisitor()
          Creates new PrettyPrintVisitor
 
Method Summary
 boolean enterComposite(Visitable host, int depth)
          Begin a visit to a composite element, with subnodes.
 void exitComposite(Visitable host)
          End a visit to a composite element, with subnodes
 void visitLeaf(Visitable host, int depth)
          Make an entire visit to a terminal node
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

PrettyPrintVisitor

public PrettyPrintVisitor()
Creates new PrettyPrintVisitor
Method Detail

visitLeaf

public void visitLeaf(Visitable host,
                      int depth)
Make an entire visit to a terminal node
Specified by:
visitLeaf in interface Visitor
Parameters:
host - node to be visited
depth - depth of traversal (starting at 0)

enterComposite

public boolean enterComposite(Visitable host,
                              int depth)
Begin a visit to a composite element, with subnodes. Return false to just treat it as a terminal.
Note that either this method or exitComposite(), depending on implementation, must do the actual visit to the composite, as visit() will never be called on this node unless this method returns false.
Specified by:
enterComposite in interface Visitor
Parameters:
host - Node accepting the Visitor
depth - current depth in traversal, starting at 0.
Returns:
true to treat this as a composite, and traverse any children; false to treat it as a terminal, ignoring any children.

exitComposite

public void exitComposite(Visitable host)
End a visit to a composite element, with subnodes
Specified by:
exitComposite in interface Visitor
Parameters:
host - node visited


Rod Johnson and Spring contributors 2001-2003.