Java: Comparing ArrayList item to User Input String

Question

I have seen other threads on this, but I still don't understand the best approach. Issue is as started: One can't compare user input that is a String to an arrayList item (object). My List will be over 40 items.

So when I try to compare classesList.get(0) to the user input mage. It won't work.

List<String> classesList = new ArrayList<String>();
classesList.add("mage");
classesList.add("warrior");
classesList.add("thief"); 

Scanner input = new Scanner(System.in);

String input = input.next();

for (int counter = 0; counter < classesList.size(); counter++) { 
    if (input == classesList.get(counter)) {
        //won't run body since can't compare
    }
}

I found some who converted the arrayList to be a String. But I am unsure how I could then easily search through my list. I'd much rather leave it as a List instead. Is the best method to this approach?

String[] classesArray = classesList.toArray(new String[classesList.size()]);

Answer 1

I think you have to see if input string exist in the ArrayList, you have to use contains() method.

   if(classesList.contains(input)) {
       //Found in the arraylist.
   }

But with you method, you can't compare strings using == operator. You should use equals() method for comparision

List<String> classesList = new ArrayList<String>();
classesList.add("mage");
classesList.add("warrior");
classesList.add("thief"); 

Scanner input = new Scanner(System.in);

String input = input.next();
boolean isExist = false;
for (String item : classesList) { 
    if (input.equals(classesList.get(counter))) {
        //Your logic if it's there.
         isExist = true;
         break;
   }
}

 if(isExist) {
     //Found in the arraylist.
 }

Also if you want to make this comparision with ingnoring the case, you shoudl consider using equlasIgnoreCase() method instead of equals() method.