Simple scanner problem

I'm using this method to read records from a file in my root project directory, storing them into an array of objects.

example of a line of text:
Texas Austin TX19759614Southwest 5

this is the method i'm using:

Code :

---

    public void readStates() {
 
        File file = new File("States.Fall2009.txt");
 
        try {
 
            Scanner console = new Scanner(file);
            Scanner lineTokenizer;
            int lineNum = 0;
 
            while (console.hasNextLine()) {
                lineTokenizer = new Scanner(console.nextLine());
                lineNum++;
 
                if (lineTokenizer.hasNext())
                    a[lineNum].name = lineTokenizer.next();
                else {
                    System.out.printf("line %d: State field is invalid", lineNum);
                    continue;
                }
 
etc...etc...etc...

---

can anyone help me out with this?

I'd say it's cause a hasn't been declared. Other than that, I can't really see anything else wrong (I'm assuming you're closing the curly brackets at the bottom somewhere, and have the appropriate catch block).

i feel like i already have, this time i'll include all of what i have so far, here it is:

Code :

---

import java.io.File;
import java.io.FileNotFoundException;
import java.util.Scanner;
 
/**
 *
 * @author Ryan
 */
 
class State {
 
    public String name;
    public String capital;
    public String symbol;
    public int number;
    public String location;
    public int locationNumber;
 
    public State(String nm, String cap, String sym, int num,
            String loc, int locNum) {
        name = nm;
        capital = cap;
        symbol = sym;
        number = num;
        location = loc;
        locationNumber = locNum;
    }
 
}
 
class ClassDataArray {
    private State[] a;
    private int nElems;
 
    public ClassDataArray(int max) {
        a = new State[max];
        nElems = 0;
    }
 
    public void print() {
        int i = 0;
        a = new State[50];
 
        for (i=0; i<a.length; i++)
            System.out.printf("%15s%15s%15s%3s%8d%16s%2d", a[i].name, a[i].capital, a[i].symbol, a[i].number, a[i].location, a[i].locationNumber);
    }
 
    public void readStates() {
 
        File file = new File("States.Fall2009.txt");
 
        try {
 
            Scanner console = new Scanner(file);
            Scanner lineTokenizer;
            int lineNum = 0;
 
            while (console.hasNextLine()) {
                lineTokenizer = new Scanner(console.nextLine());
                lineNum++;
 
                if (lineTokenizer.hasNext())
                    a[lineNum].name = lineTokenizer.next();
                else {
                    System.out.printf("line %d: State field is invalid", lineNum);
                    continue;
                }
 
                if (lineTokenizer.hasNext())
                    a[lineNum].capital = lineTokenizer.next();
                else {
                    System.out.printf("line %d: Capital field is invalid", lineNum);
                    continue;
                }
 
                if (lineTokenizer.hasNext())
                    a[lineNum].symbol = lineTokenizer.next();
                else {
                    System.out.printf("line %d: State symbol field is invalid", lineNum);
                    continue;
                }
 
                if (lineTokenizer.hasNextInt())
                    a[lineNum].number = lineTokenizer.nextInt();
                else {
                    System.out.printf("line %d: State number field is invalid", lineNum);
                    continue;
                }
 
                if (lineTokenizer.hasNext())
                    a[lineNum].location = lineTokenizer.next();
                else {
                    System.out.printf("line %d: State location field is invalid", lineNum);
                    continue;
                }
 
                if (lineTokenizer.hasNextInt())
                    a[lineNum].locationNumber = lineTokenizer.nextInt();
                else {
                    System.out.printf("line %d: Location number field is invalid", lineNum);
                    continue;
                }
            }
         } catch (FileNotFoundException e) {
             e.printStackTrace();
         }
 
    }
}
 
public class Main {
 
    public static void main(String[] args) {
        ClassDataArray arr;
        arr = new ClassDataArray(50);
 
        arr.readStates();
        arr.print();
    }
}

---

thank you for your help

"run:
Exception in thread "main" java.lang.NullPointerException
at project1.ClassDataArray.readStates(Main.java:65)
at project1.Main.main(Main.java:119)
Java Result: 1
BUILD SUCCESSFUL (total time: 0 seconds)
"

that is my error code and line 65 is

Code :

---

a[lineNum].name = lineTokenizer.next();

---

and line 119 is

Code :

---

arr.readStates();

---

Ahh, i see your problem. You initialized an array of states, but the array contains all nulls. Change that line of code to this (line 65):

Code :

---

a[lineNum].name = new State();
a[lineNum].name = lineTokenizer.next();

---

I also would add an empty constructor to the State class.

Another thing I noticed is that you advanced lineNum before putting stuff into the state. This will give you an error if you try reading in max # of states.