001 /*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements. See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License. You may obtain a copy of the License at
008 *
009 * http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017
018 package org.apache.commons.math3.geometry.euclidean.oned;
019
020 import java.io.Serializable;
021
022 import org.apache.commons.math3.exception.MathUnsupportedOperationException;
023 import org.apache.commons.math3.exception.util.LocalizedFormats;
024 import org.apache.commons.math3.geometry.Space;
025
026 /**
027 * This class implements a one-dimensional space.
028 * @version $Id: Euclidean1D.java 1416643 2012-12-03 19:37:14Z tn $
029 * @since 3.0
030 */
031 public class Euclidean1D implements Serializable, Space {
032
033 /** Serializable version identifier. */
034 private static final long serialVersionUID = -1178039568877797126L;
035
036 /** Private constructor for the singleton.
037 */
038 private Euclidean1D() {
039 }
040
041 /** Get the unique instance.
042 * @return the unique instance
043 */
044 public static Euclidean1D getInstance() {
045 return LazyHolder.INSTANCE;
046 }
047
048 /** {@inheritDoc} */
049 public int getDimension() {
050 return 1;
051 }
052
053 /** {@inheritDoc}
054 * <p>
055 * As the 1-dimension Euclidean space does not have proper sub-spaces,
056 * this method always throws a {@link MathUnsupportedOperationException}
057 * </p>
058 * @return nothing
059 * @throws MathUnsupportedOperationException in all cases
060 */
061 public Space getSubSpace() throws MathUnsupportedOperationException {
062 throw new MathUnsupportedOperationException(LocalizedFormats.NOT_SUPPORTED_IN_DIMENSION_N, 1);
063 }
064
065 // CHECKSTYLE: stop HideUtilityClassConstructor
066 /** Holder for the instance.
067 * <p>We use here the Initialization On Demand Holder Idiom.</p>
068 */
069 private static class LazyHolder {
070 /** Cached field instance. */
071 private static final Euclidean1D INSTANCE = new Euclidean1D();
072 }
073 // CHECKSTYLE: resume HideUtilityClassConstructor
074
075 /** Handle deserialization of the singleton.
076 * @return the singleton instance
077 */
078 private Object readResolve() {
079 // return the singleton instance
080 return LazyHolder.INSTANCE;
081 }
082
083 }