Class BoundFunction<T>

java.lang.Object
org.apache.commons.functor.adapter.BoundFunction<T>
Type Parameters:
T - the returned value type.
All Implemented Interfaces:
Serializable, Function<T>, Functor, NullaryFunctor
public final class BoundFunction<T> extends Object implements Function<T>, Serializable
Adapts a UnaryFunction to the Function interface using a constant unary argument.

Note that although this class implements Serializable, a given instance will only be truly Serializable if the underlying objects are. Attempts to serialize an instance whose delegates are not Serializable will result in an exception.

Version:
$Revision$ $Date$
See Also:

  • Field Details

  • Constructor Details

    • BoundFunction

      public <A> BoundFunction(UnaryFunction<? super A, ? extends T> function, A arg)
      Create a new BoundFunction instance.
      Type Parameters:
      A - the argument value type
      Parameters:
      function - the function to adapt
      arg - the constant argument to use

  • Method Details

    • evaluate

      public T evaluate()
      Evaluate this function.
      Specified by:
      evaluate in interface Function<T>
      Returns:
      the T result of this evaluation

    • equals

      public boolean equals(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 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:

    • equals

      public boolean equals(BoundFunction<?> that)
      Learn whether another BoundFunction is equal to this.
      Parameters:
      that - BoundFunction 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 Object
      Returns:
      a hash code for this functor
      See Also:

    • toString

      public 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 Object
      Returns:
      a human readable description of this functor

    • bind

      public static <A,T> BoundFunction<T> bind(UnaryFunction<? super A, ? extends T> function, A arg)
      Adapt the given, possibly-null, UnaryFunction to the Function interface by binding the specified Object as a constant argument. When the given UnaryFunction is null, returns null.
      Type Parameters:
      A - input type
      T - result type
      Parameters:
      function - the possibly-null UnaryFunction to adapt
      arg - the object to bind as a constant argument
      Returns:
      a BoundFunction wrapping the given UnaryFunction, or null if the given UnaryFunction is null