Commons Lang、CharRange#contains

import org.apache.commons.lang.CharRange;

public class C2009061500 {
    public static void main(String[] args) {
        System.out.println(new CharRange('a', 'c').contains(new CharRange('a')));
        System.out.println(new CharRange('a', 'c').contains(new CharRange('a', 'b')));
        System.out.println(new CharRange('a', 'c').contains(new CharRange('a', 'c')));
        System.out.println(new CharRange('a', 'c').contains(new CharRange('a', 'd')));
    }
}

で、

true
true
true
false