src/org/kocakosm/pitaya/charset/ASCII.java
public static boolean isAlphaNumeric(String str)
	{
		for (char c : str.toCharArray()) {
			if (!isDigit(c) && !isLetter(c)) {
				return false;
			}
		}
		return true;
	}
public static boolean isAlphaNumeric(String str)
	{
		for (char c : str.toCharArray()) {
			if (!isDigit(c) && !isLetter(c)) {
				return false;
			}
		}
		return true;
	}
Returns whether the given {@code String} is an alphanumeric sequence,
that is, a sequence which only contains letters and digits.

@param str the {@code String} to test.

@return whether the given {@code String} is an alphanumeric sequence.

@throws NullPointerException if {@code str} is {@code null}.