btree

Class BTnode<E>

java.lang.Object

btree.BTnode<E>

public class BTnode<E>
extends java.lang.Object

A BTnode provides a node for a binary tree. Each node contains a piece of data (which is a reference to an E object) and references to a left and right child. The references to children may be null to indicate that there is no child. The reference stored in a node can also be null.

Version:

April 2007

Author:

Beth Katz - changed name to be BTnode (Binary Tree node) - shortened to be the methods that belong to the class and must have instance variables to do their tasks - supporting methods such as traversals and prints are in Btree class - added Visitor interface that requires that a visit method be provided to define what action is done when a BTnode is visited

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static interface	BTnode.Visitor<E> This interface forces users of BTnode to provide a visit method to specify how a node's data is handled when it is "visited".

Constructor Summary

Constructors

Constructor and Description
BTnode(E initialData) Initialize a BTnode with a specified initial data and no children.
BTnode(E initialData, BTnode<E> initialLeft) Initialize a BTnode with a specified initial data and link to left child.
BTnode(E initialData, BTnode<E> initialLeft, BTnode<E> initialRight) Initialize a BTnode with a specified initial data and links children.

Method Summary

Modifier and Type	Method and Description
E	getData() Accessor method to get the data from this node.
BTnode<E>	getLeft() Accessor method to get a reference to the left child of this node.
BTnode<E>	getRight() Accessor method to get a reference to the right child of this node.
void	setData(E newData) Modification method to set the data in this node.
void	setLeft(BTnode<E> newLeft) Modification method to set the link to the left child of this node.
void	setRight(BTnode<E> newRight) Modification method to set the link to the right child of this node.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

BTnode

public BTnode(E initialData,
              BTnode<E> initialLeft,
              BTnode<E> initialRight)

Initialize a BTnode with a specified initial data and links children. Note that a child link may be the null reference, which indicates that the new node does not have that child.

Parameters:

initialData - the initial data of this new node

initialLeft - a reference to the left child of this new node--this reference may be null to indicate that there is no node after this new node.

initialRight - a reference to the right child of this new node--this reference may be null to indicate that there is no node after this new node. Postcondition: This node contains the specified data and links to its children.

BTnode

public BTnode(E initialData,
              BTnode<E> initialLeft)

Initialize a BTnode with a specified initial data and link to left child. Note that a child link may be the null reference, which indicates that the new node does not have that child. Right child is set to null.

Parameters:

initialData - the initial data of this new node

initialLeft - a reference to the left child of this new node--this reference may be null to indicate that there is no node after this new node. Postcondition: This node contains the specified data and links to its children.

BTnode

public BTnode(E initialData)

Initialize a BTnode with a specified initial data and no children.

Parameters:

initialData - the initial data of this new node Postcondition: This node contains the specified data and no children.

Method Detail

getData

public E getData()

Accessor method to get the data from this node.

Parameters:

- - none

Returns:

the data from this node

getLeft

public BTnode<E> getLeft()

Accessor method to get a reference to the left child of this node.

Parameters:

- - none

Returns:

a reference to the left child of this node (or the null reference if there is no left child)

getRight

public BTnode<E> getRight()

Accessor method to get a reference to the right child of this node.

Parameters:

- - none

Returns:

a reference to the right child of this node (or the null reference if there is no right child)

setData

public void setData(E newData)

Modification method to set the data in this node.

Parameters:

newData - the new data to place in this node Postcondition: The data of this node has been set to newData.

setLeft

public void setLeft(BTnode<E> newLeft)

Modification method to set the link to the left child of this node.

Parameters:

newLeft - a reference to the node that should appear as the left child of this node (or the null reference if there is no left child for this node) Postcondition: The link to the left child of this node has been set to newLeft. Any other node (that used to be the left child) is no longer connected to this node.

setRight

public void setRight(BTnode<E> newRight)

Modification method to set the link to the right child of this node.

Parameters:

newRight - a reference to the node that should appear as the right child of this node (or the null reference if there is no right child for this node) Postcondition: The link to the right child of this node has been set to newRight. Any other node (that used to be the right child) is no longer connected to this node.