Java: how to get Iterator from String [duplicate]

Answer 1

It doesn't exist, but it's trivial to implement:

class CharacterIterator implements Iterator {

    private final String str;
    private int pos = 0;

    public CharacterIterator(String str) {
        this.str = str;
    }

    public boolean hasNext() {
        return pos < str.length();
    }

    public Character next() {
        return str.charAt(pos++);
    }

    public void remove() {
        throw new UnsupportedOperationException();
    }
}

The implementation is probably as efficient as it gets.