package learnExercise;

public class RandomCharacter {

    public static char getRandomCharacter(char ch1,char ch2){

        return (char)(ch1+Math.random()*(ch2-ch1+1));//因为random<1.0，所以需要+1，才能取到ch2

    }

    public static char getRandomLowerCaseLetter(){

        return getRandomCharacter('a','z');

    }

    public static char getRandomUpperCaseLetter(){

        return getRandomCharacter('A','Z');

    }

    public static char getRandomDigitLetter(){

        return getRandomCharacter('0','9');

    }

    public static char getRandomCharacter(){

        return getRandomCharacter('\u0000','\uFFFF');

    }

}