Please help with this code Add a method int getSize to Binar

Please help with this code.

Add a method int getSize() to BinaryTree that returns the size of the binary tree where the size of the tree is defined to be the number of nodes. Here is how I want you to implement this method. Write a local class named Counter which implements the BinaryTree Visitor<E> interface:

Here is the BinaryTreeNode.java code to modify/edit:

public interface BinaryTreeNode<E>
{
E getData();
void setData(E data);
BinaryTreeNode<E> getParent();
BinaryTreeNode<E> getLeft();

void setLeft(BinaryTreeNode<E> child);
/**
* Returns the right child of this node, or null if it does
* not have one.
*/
BinaryTreeNode<E> getRight();
/**
* Removes child from its current parent and inserts it as the
* right child of this node. If this node already has a right
* child it is removed.
* @exception IllegalArgumentException if the child is
* an ancestor of this node, since that would make
* a cycle in the tree.
*/
void setRight(BinaryTreeNode<E> child);
void removeFromParent();
/**
* Visits the nodes in this tree in preorder.
*/
void traversePreorder(Visitor visitor);
void traversePostorder(Visitor visitor);
/**
* Visits the nodes in this tree in inorder.
*/
void traverseInorder(Visitor visitor);
/**
* Simple visitor interface.
*/
public interface Visitor {
<E> void visit(BinaryTreeNode<E> node);
}
}

5.3 (Include your modified BinaryTree.java source code file in your homework solution zip archive) Add a method int getSize C) to Binary Tree that returns the size of the binary tree where the size of the tree is defined to be the number of nodes. Here is how I want you to implement this method. Write a local class (see Week 9 Objects and Classes II Section 2) in getSize named Counter which implements the Binary Tree Visitor interface: nterface Counter implements Binary TreeVisitor -m Count: int visit (pData: E): void getCount(): int +visit(pData: E): void The Counter constructor initializes m Count to 0. visit simply increments mCount when it is called. Once the local t() class is completed, we can count the nodes in the tree by performing a traversal (it does not matter which type of traversal we performe because each mode will be visited during the traversal; the order in which we visit them does not matter for this application). To perform the traversal write: public int getsize Implement local class named Counter here \'777 Counter counter new Counter traverse (LEVEL ORDER, counter); return counter. getCount O

Solution

//Here the implementation of getSize() method in which local class Counter is implemented.

//Add this method to your BinaryTree.java file.

//There is no need make changes in BinaryTreeNode class file.

//Since BinaryTreeNode is implemented by BinaryTree.

public int getSize()
{
   class Counter implements BinaryTreeVisitor<E>
   {
       int count;
       Counter()
       {
           count=0;
       }
       int getCount()
       {
           return count;
       }
       void visit(E e)
       {
           count++;
       }

   }
   Counter counter=new Counter();

//Here root is head node in tree

//You must need to maintain root node in BinaryTree class.
   traverse(root,counter); //Calls the traverse method which visit each node in tree.
   return counter.getCount();
}

//Here the implemetation of inorder traversal for your reference.
void traverse(BinaryTreeNode<E> root,Counter counter)
{
          if(root == null)
            return;

        Stack<BinaryTreeNode<E>> stack = new Stack<BinaryTreeNode>();
        //define a pointer to track nodes
        BinaryTreeNode<E> p = root;

        while(!stack.empty() || p != null){

            // if it is not null, push to stack
            //and go down the tree to left
            if(p != null){
                stack.push(p);
                p = p.left;

            // if no left child
            // pop stack, process the node
            // then let p point to the right
            }else{
                BinaryTreeNode<E> t = stack.pop();
                //lst.add(t.val);
                counter.visit(t); //Visit the node in a tree by calling visit method of Counter local class
                p = t.right;
            }
        }

}