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.data;
031
032/**
033 * A source which returns data of type DATATYPE. Classes which implement this
034 * interface must support random access to rows as well as the ability to get
035 * random subsets of data.
036 *
037 * @author Jonathon Hare (jsh2@ecs.soton.ac.uk)
038 * @author Sina Samangooei (ss@ecs.soton.ac.uk)
039 *
040 * @param <DATATYPE>
041 *            the data type which can be returned
042 */
043public interface DataSource<DATATYPE> extends Iterable<DATATYPE> {
044        /**
045         * Get data between given rows. startRow must be > 0, stopRow must be
046         * smaller than {@link DataSource#size()}.
047         *
048         * data is guaranteed to have (stopRow - startRow) valid entries
049         *
050         * @param startRow
051         *            where to start (inclusive)
052         * @param stopRow
053         *            where to stop (exclusive)
054         * @param data
055         *            the array to fill
056         */
057        public void getData(int startRow, int stopRow, DATATYPE[] data);
058
059        /**
060         * Get the data for a given row
061         *
062         * @param row
063         *            the row number
064         * @return the data for the row
065         */
066        public DATATYPE getData(int row);
067
068        /**
069         * @return Number of dimensions of each data point
070         */
071        public int numDimensions();
072
073        /**
074         * @param data
075         *            a random set of data. This array is guaranteed to be filled.
076         */
077        public void getRandomRows(DATATYPE[] data);
078
079        /**
080         * @return the number of data points
081         */
082        public int size();
083
084        /**
085         * Create a temporary array suitable for use with the
086         * {@link #getRandomRows(Object[])} and {@link #getData(int, int, Object[])}
087         * methods.
088         *
089         * @param size
090         *            the size of the array
091         * @return the array
092         */
093        public DATATYPE[] createTemporaryArray(int size);
094}