001/* 002 * Copyright (C) 2014 The Guava Authors 003 * 004 * Licensed under the Apache License, Version 2.0 (the "License"); 005 * you may not use this file except in compliance with the License. 006 * You may obtain a copy of the License at 007 * 008 * http://www.apache.org/licenses/LICENSE-2.0 009 * 010 * Unless required by applicable law or agreed to in writing, software 011 * distributed under the License is distributed on an "AS IS" BASIS, 012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 013 * See the License for the specific language governing permissions and 014 * limitations under the License. 015 */ 016 017package com.google.common.graph; 018 019import com.google.common.annotations.Beta; 020import com.google.errorprone.annotations.CanIgnoreReturnValue; 021 022/** 023 * A subinterface of {@link Graph} which adds mutation methods. When mutation is not required, users 024 * should prefer the {@link Graph} interface. 025 * 026 * @author James Sexton 027 * @author Joshua O'Madadhain 028 * @param <N> Node parameter type 029 * @since 20.0 030 */ 031@Beta 032public interface MutableGraph<N> extends Graph<N> { 033 034 /** 035 * Adds {@code node} if it is not already present. 036 * 037 * <p><b>Nodes must be unique</b>, just as {@code Map} keys must be. They must also be non-null. 038 * 039 * @return {@code true} if the graph was modified as a result of this call 040 */ 041 @CanIgnoreReturnValue 042 boolean addNode(N node); 043 044 /** 045 * Adds an edge connecting {@code nodeU} to {@code nodeV} if one is not already present. 046 * 047 * <p>If the graph is directed, the resultant edge will be directed; otherwise, it will be 048 * undirected. 049 * 050 * <p>If {@code nodeU} and {@code nodeV} are not already present in this graph, this method will 051 * silently {@link #addNode(Object) add} {@code nodeU} and {@code nodeV} to the graph. 052 * 053 * @return {@code true} if the graph was modified as a result of this call 054 * @throws IllegalArgumentException if the introduction of the edge would violate {@link 055 * #allowsSelfLoops()} 056 */ 057 @CanIgnoreReturnValue 058 boolean putEdge(N nodeU, N nodeV); 059 060 /** 061 * Adds an edge connecting {@code endpoints} (in the order, if any, specified by {@code 062 * endpoints}) if one is not already present. 063 * 064 * <p>If this graph is directed, {@code endpoints} must be ordered and the added edge will be 065 * directed; if it is undirected, the added edge will be undirected. 066 * 067 * <p>If this graph is directed, {@code endpoints} must be ordered. 068 * 069 * <p>If either or both endpoints are not already present in this graph, this method will silently 070 * {@link #addNode(Object) add} each missing endpoint to the graph. 071 * 072 * @return {@code true} if the graph was modified as a result of this call 073 * @throws IllegalArgumentException if the introduction of the edge would violate {@link 074 * #allowsSelfLoops()} 075 * @throws IllegalArgumentException if the endpoints are unordered and the graph is directed 076 * @since 27.1 077 */ 078 @CanIgnoreReturnValue 079 boolean putEdge(EndpointPair<N> endpoints); 080 081 /** 082 * Removes {@code node} if it is present; all edges incident to {@code node} will also be removed. 083 * 084 * @return {@code true} if the graph was modified as a result of this call 085 */ 086 @CanIgnoreReturnValue 087 boolean removeNode(N node); 088 089 /** 090 * Removes the edge connecting {@code nodeU} to {@code nodeV}, if it is present. 091 * 092 * @return {@code true} if the graph was modified as a result of this call 093 */ 094 @CanIgnoreReturnValue 095 boolean removeEdge(N nodeU, N nodeV); 096 097 /** 098 * Removes the edge connecting {@code endpoints}, if it is present. 099 * 100 * <p>If this graph is directed, {@code endpoints} must be ordered. 101 * 102 * @throws IllegalArgumentException if the endpoints are unordered and the graph is directed 103 * @return {@code true} if the graph was modified as a result of this call 104 * @since 27.1 105 */ 106 @CanIgnoreReturnValue 107 boolean removeEdge(EndpointPair<N> endpoints); 108}