Tree,Nodes,Type of Trees

Question

I want to create a tree that detect if the insert is a Object of type Characters it will compare each one and decide where to insert [ right or left ],( i know it can detect by position in ascii table) ,and if the insert is an object of int it will do the same operation.
My Questions:
1. I need to create the tree and on the same time to set a compartor ( for example if its a tree of Chars it will be a Chars_comperator that checks Chars and he implements Comparator ( of java ).? 2. My code now is good for int only. becuase i take the object convert to string and then to int and after all this i compare and decide where to insert, this is how i need to do it? or there is another way to do it that can take care all of kinds of Objects? Here is my code and how i create the tree,

Tree class

public class tree {

bNode root;
public tree() {
    this.root = null;
}
public boolean isEmpty(){
    return root==null;
}
public void insert(Object data)
{
    if(isEmpty())
        this.root = new bNode(data);
    else
        this.root.insert(data);

   }
 }

bNode Class

public class bNode {
 protected Object data;
 protected bNode left;
 protected bNode right;


public bNode(Object data) {
    this.data = data;
    this.left = null;
    this.right = null;
}

public void insert(Object data){

    if(Integer.parseInt(data.toString())<Integer.parseInt(this.data.toString())){
        if(this.left==null)
             this.left = new bNode(data);
        else 
            this.left.insert(data);

    }
    else{
        if(this.right==null)
             this.right = new bNode(data);
        else 
            this.right.insert(data);



    }
}

Main class

public class Main {

/**
 * @param args
 */
public static void main(String[] args) {
    tree x = new tree();
    char a = 'G';
    x.insert(a);
    x.insert(60);
    x.insert(40);
    x.insert(30);
    x.insert(59);
    x.insert(61);
    x.root.printTree(x.root);


}

}
Thanks!

Answer 1

instead of passing an Object, you could pass a Comparable in insert(). Standard type like Integer, String, etc. already implement the Conparable interface.

instead of using if (a <b) you call

compareTo(a,b);

See java doc of Comparable.

If, for any reason, you want to stay with Passing an Object to insert(), you also can solve that by not using toString, but by checking the class of object, and then casting:

if (object instanceof Integer) {
    int val = ((Integer) object).intValue();
    // now compare 
} else if (object instance of String) {
     String val .....
    // use val.compareTo()
}