Programme Producing NullPointerException

Am new to programming and am trying to create a system that is similar to a train timetable system.I want the user to be able to enter the stops between two stations ( from a preset list of 5 stations ) and this be saved as an array list, and this array list be saved accordingly within a 2D array so if they were to look in [1][2] there would be an arraylist of stops between station 1 and 2.I used this to initialise the array of arraylists (in a class i created called stops)

ArrayList<String>[][] stopsArray= (ArrayList<String>[][])new ArrayList[5][5];
 
public void stops(){
for (int i = 0; i<5; i++){
for (int j=0; j<5; j++){
stopsArray[i][j]= new ArrayList<String>();
}
}
}

Then I use this code to set the stops

public void setNoStops(int stopsNo){
noOfStops = stopsNo;
}
 
[code]...

The bottom written line of code is mentioned in the null pointer error I recieve. Then.Then in my main programme I declare the new object and use these methods the method options displays the list of five stations with a number reference

System.out.println("Please choose a start station :");
options();
place1 = scanner.nextInt();
System.out.println();
 
System.out.println("Please choose an end station :");
options();
place2 = scanner.nextInt();
System.out.println();

[code]...

mystops is the object I created to store the information.

when compiling I recieve no errors.when I run the program it runs smoothly, asks for the number of stops, allows the user to enter a number, then says enter stop 1, I enter a word and the program crashes giving the error java.lang.NullPointerException