Question

I have been making a little program that needs to read a list of golf courses that could be changeing and needs to be called when ever. Here is the code:

    public class Courses {
public String[] courselist;
public void loadCourses() throws IOException{
    int count = 0;
    int counter = 0;
    File f = new File("src//courses//courses.txt");
    BufferedReader reader = new BufferedReader(new FileReader(f));
    while(count<1){
        String s = reader.readLine();
        if(s.equalsIgnoreCase("*stop*")){
            reader.close();
            count = 5;

        }else{
            courselist[counter] = s;
            counter++;
        }
        s = "";
    }
}

}

And now this is what is in the txt file.

    RiverChase 
    Steward Peninsula 
    Lake Park 
    Coyote Ridge 
    *stop* 

Now when ever i start to run the program because i call the method instantly it gives me a throw exeption and it is because of the array. And i need to stay and array because i use it in a JComboBox. If you can help or fix the problem. Most likely im just doing it wrong, im a noob. Just help. Thanks in advance.
I know all the file reader and stuff works because it prints out to the system correct, i just need help writing it to the array repetedly.

Answer 1

Change your code to assign a new array during loadCourses(), and add a call to loadCourses() to your constructor:

public class Courses {
    public String[] courselist;

    public Courses() throws IOException {  // <-- Added constructor
        loadCourses();                     // <-- Added call to loadCourses
    }

    public void loadCourses() throws IOException {
        int count = 0;
        int counter = 0;
        File f = new File("src//courses//courses.txt");
        BufferedReader reader = new BufferedReader(new FileReader(f));
        List<String> courses = new ArrayList<String>(); // <-- A List can grow 
        while(true){
            String s = reader.readLine();
            if (s.equalsIgnoreCase("*stop*")){
                break;
            }
            courses.add(s);
        }
        courseList = courses.toArray(new String[0]); // <-- assign it here
    }
}

This ensures that when you create an instance, it starts out life with the array initialised. Not only will you not get an error, but the data will always be correct (unlike other answers that simply create an empty (ie useless) array.

Note that this code will work with any number of course names in the file (not just 5).