Package org.apache.commons.functor.core

Class IsEqual<L,​R>

  • Type Parameters:
    L - the left argument type.
    R - the right argument type.
    All Implemented Interfaces:
    java.io.Serializable, BinaryFunctor<L,​R>, BinaryPredicate<L,​R>, Functor
    public final class IsEqual<L,​R>
extends java.lang.Object
implements BinaryPredicate<L,​R>, java.io.Serializable
    Tests true iff its arguments are equal or both null.

    This relation is an equivalence relation on the set of objects that adhere to the Object.equals contract.

    Version:
    $Revision$ $Date$
    See Also:
    Serialized Form

    • Field Summary

      Fields 
      Modifier and Type Field Description
      static IsEqual<java.lang.Object,​java.lang.Object> INSTANCE
      Basic IsEqual instance.
      private static long serialVersionUID
      serialVersionUID declaration.

    • Constructor Summary

      Constructors 
      Constructor Description
      IsEqual()
      Create a new IsEqual.

    • 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.
      int hashCode()
      Returns a hash code for this functor adhering to the general Object.hashCode contract.
      static <L,​R>
      IsEqual<L,​R>      		 instance()
      Get an IsEqual instance.
      boolean test​(L left, R right)
      Evaluate this predicate.
      static <L,​R>
      UnaryPredicate<L>      		 to​(R object)
      Get an IsEqual UnaryPredicate.
      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 IsEqual<java.lang.Object,​java.lang.Object> INSTANCE
        Basic IsEqual instance.

      • serialVersionUID

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

    • Constructor Detail

      • IsEqual

        public IsEqual()
        Create a new IsEqual.

    • Method Detail

      • test

        public boolean test​(L left,
                    R right)
        Evaluate this predicate.
        Specified by:
        test in interface BinaryPredicate<L,​R>
        Parameters:
        left - the L element of the ordered pair of arguments
        right - the R element of the ordered pair of arguments
        Returns:
        the result of this test 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()

      • 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 <L,​R> IsEqual<L,​R> instance()
        Get an IsEqual instance.
        Type Parameters:
        L - the left argument type.
        R - the right argument type.
        Returns:
        IsEqual

      • to

        public static <L,​R> UnaryPredicate<L> to​(R object)
        Get an IsEqual UnaryPredicate.
        Type Parameters:
        L - the left argument type.
        R - the right argument type.
        Parameters:
        object - bound comparison object
        Returns:
        UnaryPredicate