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/* * Copyright 2011-2019 the original author or authors. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * https://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package org.springframework.data.geo; import lombok.EqualsAndHashCode; import java.io.Serializable; import java.util.Collections; import java.util.Iterator; import java.util.List; import org.springframework.data.annotation.PersistenceConstructor; import org.springframework.util.Assert; import org.springframework.util.StringUtils; /** * Value object to capture {@link GeoResult}s as well as the average distance they have. * * @author Oliver Gierke * @author Thomas Darimont * @since 1.8 */ @EqualsAndHashCode public class GeoResults<T> implements Iterable<GeoResult<T>>, Serializable { private static final long serialVersionUID = 8347363491300219485L; private final List<? extends GeoResult<T>> results; private final Distance averageDistance; /** * Creates a new {@link GeoResults} instance manually calculating the average distance from the distance values of the * given {@link GeoResult}s. * * @param results must not be {@literal null}. */ public GeoResults(List<? extends GeoResult<T>> results) { this(results, Metrics.NEUTRAL); } /** * Creates a new {@link GeoResults} instance manually calculating the average distance in the given {@link Metric} * from the distance values of the given {@link GeoResult}s. * * @param results must not be {@literal null}. * @param metric must not be {@literal null}. */ public GeoResults(List<? extends GeoResult<T>> results, Metric metric) { this(results, calculateAverageDistance(results, metric)); } /** * Creates a new {@link GeoResults} instance from the given {@link GeoResult}s and average distance. * * @param results must not be {@literal null}. * @param averageDistance must not be {@literal null}. */ @PersistenceConstructor public GeoResults(List<? extends GeoResult<T>> results, Distance averageDistance) { Assert.notNull(results, "Results must not be null!"); Assert.notNull(averageDistance, "Average Distance must not be null!"); this.results = results; this.averageDistance = averageDistance; } /** * Returns the average distance of all {@link GeoResult}s in this list. * * @return the averageDistance */ public Distance getAverageDistance() { return averageDistance; } /** * Returns the actual content of the {@link GeoResults}. * * @return */ public List<GeoResult<T>> getContent() { return Collections.unmodifiableList(results); } /* * (non-Javadoc) * @see java.lang.Iterable#iterator() */ @SuppressWarnings("unchecked") public Iterator<GeoResult<T>> iterator() { return (Iterator<GeoResult<T>>) results.iterator(); } /* * (non-Javadoc) * @see java.lang.Object#toString() */ @Override public String toString() { return String.format("GeoResults: [averageDistance: %s, results: %s]", averageDistance.toString(), StringUtils.collectionToCommaDelimitedString(results)); } private static Distance calculateAverageDistance(List<? extends GeoResult<?>> results, Metric metric) { Assert.notNull(results, "Results must not be null!"); Assert.notNull(metric, "Metric must not be null!"); if (results.isEmpty()) { return new Distance(0, metric); } double averageDistance = results.stream()// .mapToDouble(it -> it.getDistance().getValue())// .average().orElse(0); return new Distance(averageDistance, metric); } }