Question

I’m having a big issue with some nested while loops I have in my java program. From what I have debugged my code checks the second while loops statement once, then exits the loop forever. I have no clue why this is happening so I will post the code here:

while (current != null) {
        if(id == current.getMovie().getId()) {
           movieExists = true;
           movie = current;
           while (checkCurrent == movie) {
              showingPointer = checkCurrent.getMovie().getLinkHead();
              while (showingPointer != null) {
                 if (cal.compareTo(showingPointer.getShowing().getShowingCalendar()) == 0) {
                    return false;
                 }
                 showingPointer = showingPointer.getNext();
              }
              checkCurrent = checkCurrent.getNext();       
           }        
        }
        current = current.getNext();
     }

Answer 1

This statement

while (checkCurrent == movie) {

compares object reference and always false . This is not the way to compare two instances

you might want to change the code to compare values something like

 while(checkCurrent.getMovie().getId() == movie.getMovie().getId()){

Or have a equals() implemented to compare.

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