why this loop infinite loop ???

Question

case "TARTUP":
intial = new File("intialInformation.txt");
info = new Scanner(intial);
coursesNUM = info.nextInt(); // 3
sectionsNUM = info.nextInt(); // 3
studentsNUM = info.nextInt(); // 17

coursesLine = info.next();

System.out.print("The courses for this semester are:");
for (int i = 0; i < coursesNUM; i++) {
System.out.print(" " +coursesLine);

}

System.out.println("\n----------------------------------------------------------\n");
https://code.sololearn.com/c7t5OaStWdoA/?ref=app

Answer 1

It shouldn't be infinite. Did you make sure that your coursesNUM is coming through as 3 just before the for-loop starts?

I would add this line and confirm it says coursesNUM = 3.
coursesLine = info.next();
System.out.println("coursesNUM = " + coursesNUM); /**** ADD THIS ***/
System.out.print("The courses for this semester are:");

I strongly suspect your coursesNUM is far larger than 3 or the problem is outside of your snippet.

One unrelated weird thing about your code is that your loop will repeatedly print the same coursesLine. I don't know how your initialInformation.txt file is formatted but you probably want information on multiple different courses. In other words, you'll do something like coursesLine = info.next() in a loop instead of before the loop.

Answer 2

Josh Greig i am sure it is 3 and i add the full code you can see it

Answer 3

SH S, your full compile-ready code can't start with break;

Also, can you share all of your txt files so I can reproduce the issue?

If you share your email address here, I'll email you and you can reply with a zip of all your code and files.

Answer 4

Josh Greig [e-mail]

Answer 5

I emailed you and tried to add you on gmail's chat.

Answer 6

You're correct that coursesNUM is reading as 3.

You're incorrect in thinking the pasted for-loop is infinite.

You should fix how your loop prints the same coursesLine 3 times like below, though:
System.out.print("The courses for this semester are:");
for (int i = 0; i < coursesNUM; i++) {
coursesLine = info.next(); /**************** MOVE HERE **/
System.out.print(" " +coursesLine);
}

Your infinite loop is the while-loop that reads commands. You read 1 command before entering your command-reading loop. Since you never read another command, your loop never ends. You should read a new command with each iteration.

Here is a snippet from the corrected code in MainProgram.java.
Scanner input = new Scanner(commandfile);

while (input.hasNext()) {
String Command = input.next(); /********** MOVE HERE ***/
switch (Command) {

I emailed the updated MainProgram.java also to save time implementing the edits.

Answer 7

Josh Greig Now I understand, thank you so much.