Could this code potentially result in an infinite loop?

Question

Is there any value that could be assigned to the myString variable that would result in an infinite loop in the code below?

while (true) {
    if (myString.indexOf("  ") == -1) {
        break;
    }
    myString = myString.replaceAll("  ", " ");
}

Answer 1

Could this code potentially result in an infinite loop?

No. But if might throw an exception if myString is null.

If the String doesn't contain two spaces, it'll break; after the first iteration. Otherwise, it does contain two spaces, and it replaces it with one space, then, it won't have two spaces again, and it'll break;.

Answer 2

No, it won't - however the loop could be much better structured:

while (myString.indexOf("  ") != -1) {
    myString = myString.replaceAll("  ", " ");
}

Sometimes you need break in a loop, but if you don't need it you should avoid it.

A better solution of course would be to not use a loop at all, remember that replaceAll works from regex:

myString = myString.replaceAll("[ ]+", " ");

For example:

String str = "this is a   test      string with long     white space    chunks";
System.out.println(str.replaceAll("[ ]+", " "));

Try it here: http://www.tryjava8.com/app/snippets/52c19090e4b00bdc99e8a943