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.ml.annotation;
031
032import java.util.List;
033import java.util.Set;
034
035import org.openimaj.data.dataset.cache.GroupedListCache;
036import org.openimaj.data.dataset.cache.InMemoryGroupedListCache;
037
038/**
039 * Adaptor that allows a {@link BatchAnnotator} to behave like a
040 * {@link IncrementalAnnotator} by caching instances and then performing
041 * training only when {@link #annotate(Object)} is called.
042 * 
043 * @author Jonathon Hare (jsh2@ecs.soton.ac.uk)
044 * 
045 * @param <OBJECT>
046 *            Type of object
047 * @param <ANNOTATION>
048 *            Type of annotation
049 */
050public class InstanceCachingIncrementalBatchAnnotator<OBJECT, ANNOTATION>
051                extends IncrementalAnnotator<OBJECT, ANNOTATION>
052{
053        BatchAnnotator<OBJECT, ANNOTATION> batchAnnotator;
054        GroupedListCache<ANNOTATION, OBJECT> objectCache;
055        boolean isInvalid = true;
056
057        /**
058         * Construct with an in-memory cache and the given batch annotator.
059         * 
060         * @param batchAnnotator
061         *            the batch annotator
062         */
063        public InstanceCachingIncrementalBatchAnnotator(BatchAnnotator<OBJECT, ANNOTATION> batchAnnotator) {
064                this.batchAnnotator = batchAnnotator;
065                this.objectCache = new InMemoryGroupedListCache<ANNOTATION, OBJECT>();
066        }
067
068        /**
069         * Construct with the given batch annotator and cache implementation.
070         * 
071         * @param batchAnnotator
072         *            the batch annotator
073         * @param cache
074         *            the cache
075         */
076        public InstanceCachingIncrementalBatchAnnotator(BatchAnnotator<OBJECT, ANNOTATION> batchAnnotator,
077                        GroupedListCache<ANNOTATION, OBJECT> cache)
078        {
079                this.batchAnnotator = batchAnnotator;
080                this.objectCache = cache;
081        }
082
083        @Override
084        public void train(Annotated<OBJECT, ANNOTATION> annotated) {
085                objectCache.add(annotated.getAnnotations(), annotated.getObject());
086                isInvalid = true;
087        }
088
089        @Override
090        public void reset() {
091                objectCache.reset();
092                isInvalid = true;
093        }
094
095        @Override
096        public Set<ANNOTATION> getAnnotations() {
097                return objectCache.getDataset().getGroups();
098        }
099
100        @Override
101        public List<ScoredAnnotation<ANNOTATION>> annotate(OBJECT object) {
102                if (isInvalid) {
103                        batchAnnotator.train(objectCache.getDataset());
104                        isInvalid = false;
105                }
106
107                return batchAnnotator.annotate(object);
108        }
109}