Recursive, Tree Traversal methods in Java

Posted on

There are three traversal methods in Java:

Pre order- The root node is visited first.

In Order-The root node is visited after one of the sides(left or right) of a sub tree has been visited.

Post Order-The root node is visited last.

For the example below we shall assume there exists a tree node with the getName() method returning a String.

We can use the below methods to find the exact node based on the requirements specified:

public void postOrder(TreeNode t){
    
    if(t!=null){
    postOrder(t.LeftChild());
    postOrderHuffTraversal(t.RightChild());
    System.out.println(t.getName());
    
    }
  }
public void inOrder(TreeNode t){
  
  if(t!=null){
  inOrder(t.LeftChild());
  System.out.println(t.getName());
  inOrder(t.RightChild());
  
  }
}
public void preOrder(TreeNode t){
     
    if(t!=null){
    System.out.println(tn.getName());
    preOrder(t.LeftChild());
    preOrder(t.RightChild());
  
  }
}