001/**
002 * Copyright (c) 2011, The University of Southampton and the individual contributors.
003 * All rights reserved.
004 *
005 * Redistribution and use in source and binary forms, with or without modification,
006 * are permitted provided that the following conditions are met:
007 *
008 *   *  Redistributions of source code must retain the above copyright notice,
009 *      this list of conditions and the following disclaimer.
010 *
011 *   *  Redistributions in binary form must reproduce the above copyright notice,
012 *      this list of conditions and the following disclaimer in the documentation
013 *      and/or other materials provided with the distribution.
014 *
015 *   *  Neither the name of the University of Southampton nor the names of its
016 *      contributors may be used to endorse or promote products derived from this
017 *      software without specific prior written permission.
018 *
019 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
020 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
021 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
022 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
023 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
024 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
025 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
026 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
027 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
028 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
029 */
030package org.openimaj.util.function.context;
031
032import org.openimaj.util.data.Context;
033import org.openimaj.util.function.Function;
034
035/**
036 * Base class that holds the elements required to adapt something (i.e. a
037 * {@link Function}) to work around around a single element of a {@link Context}
038 * and output to a potentially different key of that {@link Context}.
039 * <p>
040 * This base class just holds the parts required for the adaption (the object
041 * being adapted, and the {@link ContextExtractor} and {@link ContextInsertor}),
042 * but doesn't actually provide any functionality.
043 *
044 * @author Sina Samangooei (ss@ecs.soton.ac.uk)
045 *
046 * @param <ADAPTED>
047 *            The type of object being adapted
048 * @param <IN>
049 *            The input type of the object being adapted
050 * @param <OUT>
051 *            The output type of the object being adapted
052 */
053public abstract class ContextAdaptor<ADAPTED, IN, OUT> {
054        protected ADAPTED inner;
055        protected ContextExtractor<IN> extract;
056        protected ContextInsertor<OUT> insert;
057
058        /**
059         * Construct with the given options.
060         *
061         * @param inner
062         *            the object being adapted
063         * @param extract
064         *            the extractor
065         * @param insert
066         *            the insertor
067         */
068        public ContextAdaptor(ADAPTED inner, ContextExtractor<IN> extract, ContextInsertor<OUT> insert) {
069                this.inner = inner;
070                this.insert = insert;
071                this.extract = extract;
072        }
073
074        /**
075         * Construct with the given object to adapt. The insertor and extractor are
076         * created from the given keys.
077         *
078         * @param inner
079         *            the object being adapted
080         * @param keyin
081         *            the key to extract from the context to produce the input for
082         *            the object
083         * @param keyout
084         *            the key to insert with the the output for the object
085         */
086        public ContextAdaptor(ADAPTED inner, String keyin, String keyout) {
087                this.inner = inner;
088                this.extract = new KeyContextExtractor<IN>(keyin);
089                this.insert = new KeyContextInsertor<OUT>(keyout);
090        }
091}