/*license*\ XBN-Java Library Copyright (c) 2014, Jeff Epstein (aliteralmind __DASH__ github __AT__ yahoo __DOT__ com) This software is dual-licensed under the: - Lesser General Public License (LGPL) version 3.0 or, at your option, any later version; - Apache Software License (ASL) version 2.0. Either license may be applied at your discretion. More information may be found at - http://en.wikipedia.org/wiki/Multi-licensing. The text of both licenses is available in the root directory of this project, under the names "LICENSE_lgpl-3.0.txt" and "LICENSE_asl-2.0.txt". The latest copies may be downloaded at: - LGPL 3.0: https://www.gnu.org/licenses/lgpl-3.0.txt - ASL 2.0: http://www.apache.org/licenses/LICENSE-2.0.txt \*license*/ package com.github.xbn.examples.lang.functor; /** <p>Implementing a <a href="http://stackoverflow.com/questions/7369460/help-with-understanding-a-function-object-or-functor-in-java/22163940#22163940">functor</a> with an Enum.</p> <p>{@code java com.github.xbn.examples.lang.functor.FunctorAsEnum1of2}</p> * @see com.github.xbn.examples.lang.functor.FunctorAsEnum2of2 * @since 0.1.0 * @author Copyright (C) 2014, Jeff Epstein ({@code aliteralmind __DASH__ github __AT__ yahoo __DOT__ com}), dual-licensed under the LGPL (version 3.0 or later) or the ASL (version 2.0). See source code for details. <a href="http://xbnjava.aliteralmind.com">{@code http://xbnjava.aliteralmind.com}</a>, <a href="https://github.com/aliteralmind/xbnjava">{@code https://github.com/aliteralmind/xbnjava}</a> **/ public class FunctorAsEnum1of2 { public static final void main(String[] ignored) { CardinalDirection.WEST.move(3); CardinalDirection.NORTH.move(2); CardinalDirection.EAST.move(15); } } enum CardinalDirection { NORTH(new MoveNorth()), SOUTH(new MoveSouth()), EAST(new MoveEast()), WEST(new MoveWest()); private final MoveInDirection dirFunc; CardinalDirection(MoveInDirection dirFunc) { if(dirFunc == null) { throw new NullPointerException("dirFunc"); } this.dirFunc = dirFunc; } public void move(int steps) { dirFunc.move(steps); } } interface MoveInDirection { void move(int steps); } class MoveNorth implements MoveInDirection { public void move(int steps) { System.out.println("Moved " + steps + " steps north."); } } class MoveSouth implements MoveInDirection { public void move(int steps) { System.out.println("Moved " + steps + " steps south."); } } class MoveEast implements MoveInDirection { public void move(int steps) { System.out.println("Moved " + steps + " steps east."); } } class MoveWest implements MoveInDirection { public void move(int steps) { System.out.println("Moved " + steps + " steps west."); } }