Package org.apache.commons.functor.core.comparator

Class ComparatorFunction<T>

  • Type Parameters:
    T - the binary function input types
    All Implemented Interfaces:
    java.io.Serializable, BinaryFunction<T,​T,​java.lang.Integer>, BinaryFunctor<T,​T>, Functor
    public final class ComparatorFunction<T>
extends java.lang.Object
implements BinaryFunction<T,​T,​java.lang.Integer>, java.io.Serializable
    Adapts a Comparator to the BinaryFunction interface.
    Version:
    $Revision$ $Date$
    See Also:
    Serialized Form

    • Field Summary

      Fields 
      Modifier and Type Field Description
      private java.util.Comparator<? super T> comparator
      The comparator to wrap.
      static ComparatorFunction<java.lang.Comparable<?>> INSTANCE
      Basic ComparatorFunction instance.
      private static long serialVersionUID
      serialVersionUID declaration.

    • Constructor Summary

      Constructors 
      Constructor Description
      ComparatorFunction​(java.util.Comparator<? super T> comparator)
      Create a new ComparatorFunction.

    • Method Summary

      All Methods Static Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      boolean equals​(java.lang.Object that)
      Indicates whether some other object is "equal to" this functor.
      boolean equals​(ComparatorFunction<?> that)
      Learn whether a specified ComparatorFunction is equal to this.
      java.lang.Integer evaluate​(T left, T right)
      Evaluate this function.
      int hashCode()
      Returns a hash code for this functor adhering to the general Object.hashCode contract.
      static <T> ComparatorFunction<T> instance()
      Get a basic ComparatorFunction instance.
      java.lang.String toString()
      Returns a human readable description of this functor.

      • Methods inherited from class java.lang.Object

        clone, finalize, getClass, notify, notifyAll, wait, wait, wait

    • Field Detail

      • INSTANCE

        public static final ComparatorFunction<java.lang.Comparable<?>> INSTANCE
        Basic ComparatorFunction instance.

      • serialVersionUID

        private static final long serialVersionUID
        serialVersionUID declaration.
        See Also:
        Constant Field Values

      • comparator

        private final java.util.Comparator<? super T> comparator
        The comparator to wrap.

    • Constructor Detail

      • ComparatorFunction

        public ComparatorFunction​(java.util.Comparator<? super T> comparator)
        Create a new ComparatorFunction.
        Parameters:
        comparator - to wrap

    • Method Detail

      • evaluate

        public java.lang.Integer evaluate​(T left,
                                  T right)
        Evaluate this function.
        Specified by:
        evaluate in interface BinaryFunction<T,​T,​java.lang.Integer>
        Parameters:
        left - the L element of the ordered pair of arguments
        right - the R element of the ordered pair of arguments
        Returns:
        the T result of this function for the given arguments

      • equals

        public boolean equals​(java.lang.Object that)
        Indicates whether some other object is "equal to" this functor. This method must adhere to general Object.equals contract. Additionally, this method can return true only if the specified Object implements the same functor interface and is known to produce the same results and/or side-effects for the same arguments (if any).

        While implementators are strongly encouraged to override the default Object implementation of this method, note that the default Object implementation does in fact adhere to the functor equals contract.

        Specified by:
        equals in interface Functor
        Overrides:
        equals in class java.lang.Object
        Parameters:
        that - the object to compare this functor to
        Returns:
        true iff the given object implements this functor interface, and is known to produce the same results and/or side-effects for the same arguments (if any).
        See Also:
        Functor.hashCode()

      • equals

        public boolean equals​(ComparatorFunction<?> that)
        Learn whether a specified ComparatorFunction is equal to this.
        Parameters:
        that - the ComparatorFunction to test
        Returns:
        boolean

      • hashCode

        public int hashCode()
        Returns a hash code for this functor adhering to the general Object.hashCode contract. Implementators are strongly encouraged but not strictly required to override the default Object implementation of this method.
        Specified by:
        hashCode in interface Functor
        Overrides:
        hashCode in class java.lang.Object
        Returns:
        a hash code for this functor
        See Also:
        Functor.equals(java.lang.Object)

      • toString

        public java.lang.String toString()
        Returns a human readable description of this functor. Implementators are strongly encouraged but not strictly required to override the default Object implementation of this method.
        Specified by:
        toString in interface Functor
        Overrides:
        toString in class java.lang.Object
        Returns:
        a human readable description of this functor

      • instance

        public static <T> ComparatorFunction<T> instance()
        Get a basic ComparatorFunction instance.
        Type Parameters:
        T - the binary function input types
        Returns:
        ComparatorFunction