Error when trying to read from files in Java

Question

I've created this code in Java which opens a file if it exists in my pc and read from it the number of words. When trying to execute NUllPointerException occurs in the line "x.hasNext() " eventhough I've created an object of x. Can someone explain this? Notice that the file already exists in my pc

import java.io.*;
import java.util.*;

public class nrFjaleve {
    private Scanner x;

    public void open(){
        try{
            x=new Scanner(new File("p.txt"));
        }
        catch(Exception e){
            System.out.println("The file doesnt exist");
        }
    }

    public void read() 
    {
        while(x.hasNext()){
            int nr=0;
            String a = x.next();
            nr++;
        }
    }

    public void close() {
        x.close();
    }



    public static void main(String[] args)
    {           
        nrFjaleve ob=new nrFjaleve();
        //ob.exist();
        ob.read();
        ob.open();
        ob.close();
    }
}