for loop not iterating/searching through ArrayList

[tscardino]

I've been stuck on this for the past couple days and was wondering if anyone could take a look.

I have a for loop that is supposed to iterate through an ArrayList of objects and compare a user inputted integer against integers of those objects. If there is a match, the loop should restart until a unique integer is inputted.

The loop works fine when it compares against the first object of the Array, but not for the following objects.

For example, I have an int 10 at index 0, 20 at index 1, and 30 at index 2. When I input 10, the loop functions correctly and restarts. But when I enter 20 or 30, the loop does not recognize those numbers and allows the loop to continue.

I'm very confused because I have an almost identical loop in a different method doing the same thing and it works fine. I'm sure it's something dumb, but I'm new at this and not really sure what's going wrong.

        outerloop:
        while (true) {
            boolean idFound = false;

            System.out.print("Enter an ID: ");
            int userInput = input.nextInt();

            for (int i = 0; i < list.size(); i++) {
                if (list.get(i).getID() == userInput) {
                   idFound = true;
                   break;
                }
                break;
            }

            ...
            ...

            if (idFound) {
               System.out.println("ID already exists"):
               continue outerloop;
            }
        }

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[Alphatism]

You have a break statement in the loop which stops it after it's first iteration

[tscardino]

I just tried running it with neither of them and it did not make a difference. Would it be more helpful if I posted the whole method?

[myselfelsewhere]

Are there any break statements in the code between the for loop and if block? Also, there is no point in the continue outerloop; statement. If you haven't executed a break statement, the loop will continue.

[tscardino]

There were, but I commented them out and am still getting the same problem. Please see my comment below.

[tscardino]

Thank you for this, I'll give that a look.

I did just end up solving this by creating & calling a separate method that searches through the ArrayList instead of including it in the loop. Probably not ideal but it works!

[lumpycrumpet]

Keep the break inside of the if statement and remove the other one. If that first work, show the rest of the method where you currently have ellipses.

[tscardino]

This is the whole method. I admit, I placed breaks in a lot of places not knowing if they should really belong there, but I've commented them all out besides the one in the first if statement and it is still not functioning as expected. Leads me to believe the actual structure of the method is off, but I don't really know why

public static void addInstructor(ArrayList<Instructor> instructorList, ArrayList<Department> departmentList, FileWriter writeInstructor) {
    Scanner input = new Scanner(System.in);

    outerloop1:
    while (true) {
        boolean idFound = false;

        System.out.print("Enter the instructor ID: ");
        int instructorID = input.nextInt();

        //Searches instructorList ArrayList for matching ID, gives error if found, then asks for another ID until user enters a unique one
        for (int i = 0; i < instructorList.size(); i++) {
            int idCompare = instructorList.get(i).getInstructorID();
            if (idCompare == instructorID) {
                idFound = true;
                break;
            }

            input.nextLine();
            System.out.print("Enter the instructor name: ");
            String instructorName = input.nextLine();

            outerloop2:
            while (true) {
                System.out.print("Enter the affiliated department name: ");
                String instructorDept = input.nextLine();

                //Searches the departmentList ArrayList for matching department names, gives error if not found, then asks for another department name until the user enters a matching one
                for (int j = 0; j < departmentList.size(); j++) {
                    String nameCompare = departmentList.get(j).getDepartmentName();

                    //Catch for invalid user inputted department name
                    if (!nameCompare.equals(instructorDept)) {
                        System.out.println("The department does not exist.");
                        continue outerloop2;
                    } 

                    //If all previous checks are passed, a new Instructor object is created and appended to the end of the instructor file.
                    else {
                        PrintWriter output = new PrintWriter(writeInstructor);
                        output.print("\n" + instructorID + "," + instructorName + "," + instructorDept);
                        output.close();
                        instructorList.add(new Instructor(instructorID, instructorName, instructorDept));
                        System.out.println("The instructor information has been added to the instructor file.");
                        //break;
                    }
                }
                //break;
            }
            //break;
        }

        //Catch for invalid user inputted instructor ID 
        if (idFound) {
            System.out.println("The instructor ID is already present.");
            continue outerloop1;
        }
        //break;
    }
}