Check if String contains only letters

Solution 1:

What do you want? Speed or simplicity? For speed, go for a loop based approach. For simplicity, go for a one liner RegEx based approach.

Speed

public boolean isAlpha(String name) {
    char[] chars = name.toCharArray();

    for (char c : chars) {
        if(!Character.isLetter(c)) {
            return false;
        }
    }

    return true;
}

Simplicity

public boolean isAlpha(String name) {
    return name.matches("[a-zA-Z]+");
}

Solution 2:

Java 8 lambda expressions. Both fast and simple.

boolean allLetters = someString.chars().allMatch(Character::isLetter);