Java ArrayList语法错误

Question

I'm getting an error when declaring this ArrayList as an instance variable in Java.

private ArrayList<char> correctGuesses = new ArrayList<char>();

The error:

Syntax error on token char, Dimension expected after this token

Can I not make ArrayLists with type char?

Answer 1

不能使用基本类型，而你使用它的包装类..所以不是char ，你将有Character

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

Answer 2

You can't use primitives as generic parameters. Instead, you use the wrapped version.
Try this:

private ArrayList<Character> correctGuesses = new ArrayList<Character>();

You can still add char types to it though, because java auto-boxes them. ie

correctGuesses.add((char)63);

would be a legal statement.

Answer 3

Declare your ArrayList using Character :

private ArrayList<Character> correctGuesses = new ArrayList<Character>();

Generics don't work with simple types, they require Objects.