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Thread: Comparator interface question

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    Default 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?


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    Default 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.

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    brisingrbrom (February 24th, 2012)

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    Default 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

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    Default 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.

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