public class DecisionTree extends BinaryTree implements DecisionTreeInterface

$\{$

private BinaryNode currentNode; $//$ Tracks where we are in the tree

public DecisionTree$()$

$\{$

$/*$ Add code to here to inherit parent class $*/$

resetCurrentNode$()$;

$\}//$ end default constructor

public DecisionTree$($T rootData$)$

$\{$

$/*$ Add code to here to inherit parent class $*/$

resetCurrentNode$()$;

$\}//$ end constructor

$/*$ Change the following code for DecisionTree as Binary Tree $*/$

public DecisionTree$()$

$\{$

$/*$ Add code to here to inherit parent class $*/$

resetCurrentNode$()$;

$\}//$ end constructor

public DecisionTree$($T rootData, T responseForNo, T responseForYes$)$

$\{$

$/*$ Change the following code for DecisionTree as BinaryTree responseForNo and responseForYes $*/$

$/*$ Add code $*/$ DecisionTree leftTree

$/*$ Add code $*/$ DecisionTree rightTree

$/*$ Add code $*/$ setTree$()$;

resetCurrentNode$()$;

$\}//$ end constructor

public T getCurrentData$()$

$\{$

if $($currentNode $!=$ null$)$

return currentNode.getData$()$;

else

return null;

$\}//$ end getCurrentData

public void setCurrentData$($T newData$)$

$\{$

if $($currentNode $!=$ null$)$

currentNode.setData$($newData$)$;

else

throw new NullPointerException$()$;

$\}//$ end setCurrentData

public void setResponses$($T responseForNo, T responseForYes$)$

$\{$

if $($currentNode $==$ null$)$

throw new NullPointerException$()$;

else if $($currentNode$.$hasLeftChild$())$

$\{$

$/*$ Add code $*/$ BinaryNode leftChild

leftChild.setData$($responseForNo$)$;

$\}$

else

$\{$

$/*$ Add code $*/$

$/*$ Add code $*/$

$\}//$ end if

if $($currentNode$.$hasRightChild$())$

$\{$

$/*$ Add code $*/$ BinaryNode rightChild

rightChild.setData$($responseForYes$)$;

$\}$

else

$\{$

$/*$ Add code $*/$ BinaryNode newRightChild

currentNode.setRightChild$($newRightChild$)$;

$\}//$ end if

$\}//$ end setResponses

public boolean isAnswer$()$

$\{$

if $($currentNode $!=$ null$)$

return currentNode.isLeaf$()$;

else

return false;

$\}//$ end isAnswer

public void advanceToNo$()$

$\{$

if $($currentNode $==$ null$)$

throw new NullPointerException$()$;

else

currentNode $=$ currentNode.getLeftChild$()$;

$\}//$ end advanceToNo

public void advanceToYes$()$

$\{$

if $($currentNode $==$ null$)$

throw new NullPointerException$()$;

else

currentNode $=$ currentNode.getRightChild$()$;

$\}//$ end advanceToYes

public void resetCurrentNode$()$

$\{$

currentNode $=$ getRootNode$()$;

$\}//$ end resetCurrentNode

protected BinaryNode getCurrentNode$()$

$\{$

return currentNode;

$\}//$ end getCurrentNode

$\}//$ end DecisionTree