Chapter 25, Problem 25.17PE

Program Plan Intro

Program Plan:

• Include the required import statement.
• Define the main class.
  • Declare the necessary variables
  • Using start initialize the required.
    • Create border pane, tree view, text field and button.
    • Set the tree view as center, alignment.
    • Add an action event to the button.
    • Create a scene and place the pane in the stage.
    • Set the title.
    • Place the scene in the stage.
    • Display the stage.
  • Define the main method using public static main.
    • Initialize the call.
  • Define “decode” method.
    • Declare the variable
    • Check the length of the “bits”.
      • If the “bits” value is “0” set that value into left subtree, if the “bits” value is “1” set the value into right subtree.
    • If the left subtree is null, leaf is detected and restart from the root.
    • Return the “result”.
  • Define “encode” method.
    • Declare and set the value.
    • Check the length of the “text”.
      • Calculate the result.
      • Return the “result”.
  • Define “getCode” method.
    • Check the “root” value is null
    • The variable “codes” is declared and allocates memory for that variable.
    • Call the “assignCode” method.
    • Return the “codes” value.
  • Define “assignCode” method.
    • Check if root of left subtree value is not null.
      • If the condition is true, calculate the left and right subtree value and call the “assignCode” method with the respective parameters.
    • Otherwise calculate the “root” element value.
  • Define “getHuffmanTree” method.
    • Create a heap to hold the trees.
    • Add the values into the heap tree.
    • If the heap tree is greater than 1, remove the smallest and next smallest weight from the tree and combine the two trees.
    • Finally return the tree.
  • Define “getCharacterFrequency” method.
    • Declare the variable.
    • The try-catch block is used to check the input file is present or not and count the number of characters in that file.
    • Return the total counts.
  • Define “TreeView” class.
    • Declare the required variables.
    • Define the constructor.
    • Define the “setTree” method.
      • Add the value.
      • Call the “repaint” method.
    • Define the “repaint” method.
      • Clear the pane
      • Display the tree recursively.
  • Define the “displayTree” method.
    • Check if the left node value is not equal to null.
      • Draw a line to the up node.
      • Draw the left subtree recursively.
    • Check if the right node value is not equal to null.
      • Draw a line to the down node.
      • Draw the left subtree recursively.
    • Display the node.
  • Define “Tree” class.
    • Declare the variable.
    • Create a tree with two subtrees,
    • Create a tree containing a leaf node.
    • Compare the trees based on their weights.
  • Define “Node” class.
    • Declare the required variables.
    • Create a default constructor.
    • Create a node with the particular weight and character.
  • Define “Heap” class.
    • Create the object for the ArrayList
    • Create the default constructor.
    • Create a heap from an array of objects.
    • Define “add” method.
      • Add the new object into the heap.
      • Check the “currentIndex” value is greater than 0.
        • Swap if the current object is greater than its parents.
        • Assign “parentIndex” value into “currentIndex” variable.
    • Define “remove” method.
      • Check the condition and remove the root from the heap.
      • Declare and compute the left and right child index.
      • Then find the maximum value between two children.
      • Swap if the current node is less than maximum value.
      • Finally return the value.