Java Comparable: helper methods for isLessThan, isGreaterThan, isEqualTo

Question

For objects a and b implementing the Comparable interface I want to avoid having code like

if (a.compareTo(b) > 0) {
    ...
}

instead, I am looking for helper methods like

if (a.isGreaterThan(b)) {
    ...
}

This would help me a lot for not always having to look up the definition of the return value of compareTo(T o):

Returns a negative integer, zero, or a positive integer as this object is less than, equal to, or greater than the specified object.

Really helpful would be 5 different methods:

Instead of                  use potential helper method:

a.compareTo(b) < 0          a.isLessThan(b)
a.compareTo(b) <= 0         a.isLessOrEqualTo(b)
a.compareTo(b) == 0         a.isEqualTo(b)
a.compareTo(b) >= 0         a.isGreaterOrEqualTo(b)
a.compareTo(b) > 0          a.isGreaterThan(b)

Are there any helper methods like this in the JDK or other libraries that provide this kind of functionality?

Answer 1

You do not need these methods if you'll remember, that it's just enough to have a mental substitution by carrying the compareTo argument to the right side of comparison as following:

a.compareTo(b) < 0    ---->   a[.compareTo(...)] < b

Since it's that simple, noone usually cares about having any better form of comparison in a library. If you still insist on some more readable form of expression, you can use default methods from Java 8 to extend Comparable interface as following:

public interface ComparableDSL<T> extends Comparable<T> {
    default boolean isLessThan(T that) { 
         return compareTo(that) < 0;
    }
}