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 */ 017package org.apache.commons.geometry.core; 018 019/** Interface representing a point in a mathematical space. 020 * 021 * <p>Implementations of this interface are sufficient to define a 022 * space since they define both the structure of the points making up 023 * the space and the operations permitted on them. The only mathematical 024 * requirement at this level is that the represented space have a defined 025 * distance metric, meaning an operation that can compute the distance 026 * between two points (ie, the space must be a metric space). 027 * </p> 028 * 029 * <p>This interface uses self-referencing generic parameters to ensure 030 * that implementations are only used with instances of their own type. 031 * This removes the need for casting inside of methods in order to access 032 * implementation-specific data, such as coordinate values. 033 * </p> 034 * 035 * @see <a href="https://en.wikipedia.org/wiki/Metric_space">Metric space</a> 036 * 037 * @param <P> Point implementation type 038 */ 039public interface Point<P extends Point<P>> extends Spatial { 040 041 /** Compute the distance between this point and another point. 042 * @param p second point 043 * @return the distance between this point and p 044 */ 045 double distance(P p); 046}