Question

I was looking at another page here on stackoverflow and came across a working implementation of cycle sort, but I don’t understand how a statement with a semicolon can exist before the curly braces in a while loop. I thought that the while loop is supposed to completely terminate and take no further actions once it finds a statement with a semicolon, so how is it that the code within the curly braces is getting executed? At first glance, I would interpret this as “var” gets incremented with each iteration of the while loop – but I know this is not the case because removing it from that spot and putting the “var++” inside of the curly braces causes an infinite loop.

Under exactly which condition is “var” incremented? Either an explanation, or a link that explains similar syntax:

while (checkSomeBool) var++;
{
   //other stuff happening in here
}

would be appreciated. Thank you. Below is the code taken from CycleSort

public static final <T extends Comparable<T>> int cycleSort(final T[] array) {
int writes = 0;

// Loop through the array to find cycles to rotate.
for (int cycleStart = 0; cycleStart < array.length - 1; cycleStart++) {
  T item = array[cycleStart];

  // Find where to put the item.
  int pos = cycleStart;
  for (int i = cycleStart + 1; i < array.length; i++)
    if (array[i].compareTo(item) < 0) pos++;

  // If the item is already there, this is not a cycle.
  if (pos == cycleStart) continue;

  // Otherwise, put the item there or right after any duplicates.
  <while (item.equals(array[pos])) pos++;
  {
    final T temp = array[pos];
    array[pos] = item;
    item = temp;
  }
  writes++;

  // Rotate the rest of the cycle.
  while (pos != cycleStart) {
    // Find where to put the item.
    pos = cycleStart;
    for (int i = cycleStart + 1; i < array.length; i++)
      if (array[i].compareTo(item) < 0) pos++;

    // Put the item there or right after any duplicates.
    while (item.equals(array[pos])) pos++;
    {
      final T temp = array[pos];
      array[pos] = item;
      item = temp;
    }
    writes++;
  }
} 
return writes;

}

Answer 1

The while loop ends with var++

while (checkSomeBool) var++; // while ends here

The code after that is not part of the while loop at all.

{
   //other stuff happening in here - not part of the while loop
}