eirikhalvard / binary-tree-to-string

Printing a binary tree

Binary tree to string

A java utility for generating formatted strings from binary trees.

Installation

To install the printer, simply add the toString method, and the TreeString class inside your BinaryTree class. These methods can be found in BinaryTree.java, where a full setup is provided.

public class BinaryTree {
  private Node root;

  private class Node {
    Node left, right;
    int value;
  }

  // add the toString method
  @Override
  public String toString() {
    // get the content from BinaryTree.java
  }

  // add the TreeString class
  private class TreeString {
    // get the content from BinaryTree.java
  }
}

The code will only work if you have the same names as above, unless you change the code.

• BinaryTree can be called something else if you want to
• Node class has to be called Node
• root has to be called root and be of type Node
• left has to be called left and be of type Node
• right has to be called left and be of type Node
• value has to be called value, but does not be of type int. Since the printer uses String.valueOf(node.value), the printer will probably work on any datatype. If it is an object, it will fall back to the objects toString method.

Usage

The file contains an override of the toString() method, and a private class that contains all the logic. Simple call the tree's toString() function, and a representation of the tree is returned.

Example print

                                +--[ 31  ]
                                |
                   +--[  50  ]--+
                   |
        +--[ 61 ]--+
        |          |
        |          |                        +--[ 89  ]--+
        |          |                        |           |
        |          |                        |           +--[ 99 ]
        |          |                        |
        |          |            +--[ 207 ]--+
        |          |            |
        |          +--[ 225  ]--+
        |                       |
        |                       +--[ 291 ]--+
        |                                   |
        |                                   +--[ 373 ]--+
        |                                               |
        |                                               +--[3513]
        |
[5767]--+
        |
        +--[6460]--+
                   |
                   |            +--[78788]--+
                   |            |           |
                   |            |           +--[91482]
                   |            |
                   +--[811201]--+