Why can't I declare an ArrayList of characters

Question

Why can't I declare an ArrayList of char, I know the String class exist but it still seem weird I can't do the following piece of code

ArrayList<char> foo = new ArrayList<char>();

Answer 1

You cannot use primitive types as a generic type-parameter; you need to use the wrapper class for char, which is Character:

List<Character> characterList = new ArrayList<>(); //Java 7

or

List<Character> characterList = new ArrayList<Character>(); //Java 5,6

This goes for any class that accepts a generic type-parameter. So for example, if you had tried to use int, you would get the same error. Instead, you would have had to use Integer.

Answer 2

Collections do not allow the use of primitive types. You'd encounter this error had you tried any of the primitives, (int, long, double, etc..). Use a primitive wrapper such as Character, to declare the collection.

ArrayList<Character> foo = new ArrayList<Character>();

Answer 3

its Character not char

List<Character> foo = new ArrayList<Character>();

From starting letter you can easily makeout that char is not class

Answer 4

Try Character,

ArrayList<Character> characterList = new ArrayList<Character>();