Why am I getting a NullPointerException in my project? - nullpointerexception

Question

This is the beginning of my project:
//class variables
private static int numberOfCouples;
//object arrays
private static Witch[] witch;
private static Wizard[] wizard;
//ranking arrays
private static int[][] witchPartnerRanking;
private static int[][] wizardPartnerRanking;
//proposal array
private static boolean[][] proposal;
//DO NOT ALTER THE MAIN METHOD
public static void main(String[] args) throws FileNotFoundException {
go( "coven_dance.txt" );
System.out.println( "Witch array:" );
for ( int i = 0; i < witch.length; i++ ) {
System.out.printf( "Witch %d:, name: %-20s, current partner id: %2d, proposals made: %d%n",
witch[ i ].getId(), witch[ i ].getName(), witch[ i ].getParnerWizardId(), witch[ i ].getNumberOfProposals() );
A NullPointerException happens on the last line. Even though I have this:
private static void go( String fileName ) throws FileNotFoundException {
//1. READ THE FILE
Scanner inStream = new Scanner( new File ( fileName ));
numberOfCouples = inStream.nextInt();
// System.out.println(howManyCouples);
//System.out.print(
inStream.nextLine();
//2. CREATE AND POPULATE THE witch ARRAY
/*Witch[]*/ witch = new Witch[numberOfCouples*2];
/*int [][]*/ witchPartnerRanking = new int[numberOfCouples*2][numberOfCouples];
for (int i = 0; i < numberOfCouples*2; i++) {
if(inStream.hasNextInt()){
//4. CREATE AND POPULATE THE witchPartnerRanking ARRAY
int j = 0;
while(inStream.hasNextInt() && j<numberOfCouples){
int prefer = inStream.nextInt();
//System.out.println(prefer);
witchPartnerRanking[i][j] = prefer;
j++;
}
String bob = inStream.nextLine();
//System.out.println(bob);
}
else{
String name = inStream.next();
//System.out.println(name);
Witch the = new Witch(i, name);
witch[i] = the;
}
}
I'm not sure what's going on. If anyone could help, that would be awesome.
Here's the file I'm reading from if you need it:
4
NannyOgg 0 2 3 1
TiffanyAching 3 2 0 1
MagratGarlick 0 3 2 1
GrannyWeatherwax 0 3 2 1
TheLibrarian 2 1 3 0
PonderStibbons 2 1 3 0
LordVetinari 1 2 0 3
DEATH 3 2 1 0

Answer 1

You witch array is being accessed without being initialized.
You have private static Witch[] witch; which is declared but not initialized
You need to initialize it. One way to do so is:
private static Witch[] witch = new Witch[10]; // replace 10 with any array size you want
In Java, arrays are treated as regular objects. Whenever you are accessing an object that is null, you get a NullPointerException.