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Comparator interface question
I have to implement a class which implements the Comparator interface which does this: Given two Comparables of identical type, give the reverse of the "natural"
ordering (from their built-in compareTo method) for those objects.
I don't really understand what it means when it says given two Comparables of identical type, can someone help me please?
Related threads:
Re: Comparator interface question
See the API for Comparable: Comparable (Java Platform SE 6)
When implementing the Comparator interface, sometimes (but definitely not always) one uses the compareTo method of Comparable ( see Object Ordering (The Java™ Tutorials > Collections > Interfaces) for examples). The above API for Comparable describes what is returned from the compareTo method, to reverse the order you can reverse the value of what is returned.
brisingrbrom (February 24th, 2012)
Re: Comparator interface question
Ok I understand that but how do I then use two of these Comparables in a Comparator interface? Syntax in Java is really confusing me and thanks for the response
Re: Comparator interface question
Many basic classes already implement the Comparable interface...for instance String, Integer, Float, Double, etc...in fact the link I provided to the API above lists all known implementing classes in the standard java library.
brisingrbrom (February 24th, 2012)
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