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Thread: Initialization of a class

  1. #1
    Junior Member
    Join Date
    Oct 2010
    Thanked 0 Times in 0 Posts

    Default Initialization of a class

    I'm trying to initialize a class like this, but I get NullPointerException. What is wrong with it?

    public class TreeNode {
    private char letter;
    private TreeNode[] link;

    public void set_letter(char letter) {
    this.letter = letter;

    public char get_letter() {
    return letter;

    public TreeNode(char c){
    // Initialize the node
    // Default value for links is NULL
    for(int i=0; i<10; i++){
    link[i] = null;

    public static void main(String[] args) throws Exception {
    TreeNode tn = new TreeNode((char)97);

    Last edited by Merik; October 28th, 2010 at 07:13 PM.

  2. #2
    Member Darryl.Burke's Avatar
    Join Date
    Mar 2010
    Madgaon, Goa, India
    Thanked 48 Times in 46 Posts

    Default Re: Initialization of a class

    I don't see where you initialize the array.


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