001/* 002 * Copyright (C) 2016 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; 021import javax.annotation.CheckForNull; 022 023/** 024 * A subinterface of {@link ValueGraph} which adds mutation methods. When mutation is not required, 025 * users should prefer the {@link ValueGraph} interface. 026 * 027 * @author James Sexton 028 * @param <N> Node parameter type 029 * @param <V> Value parameter type 030 * @since 20.0 031 */ 032@Beta 033@ElementTypesAreNonnullByDefault 034public interface MutableValueGraph<N, V> extends ValueGraph<N, V> { 035 036 /** 037 * Adds {@code node} if it is not already present. 038 * 039 * <p><b>Nodes must be unique</b>, just as {@code Map} keys must be. They must also be non-null. 040 * 041 * @return {@code true} if the graph was modified as a result of this call 042 */ 043 @CanIgnoreReturnValue 044 boolean addNode(N node); 045 046 /** 047 * Adds an edge connecting {@code nodeU} to {@code nodeV} if one is not already present, and sets 048 * a value for that edge to {@code value} (overwriting the existing value, if any). 049 * 050 * <p>If the graph is directed, the resultant edge will be directed; otherwise, it will be 051 * undirected. 052 * 053 * <p>Values do not have to be unique. However, values must be non-null. 054 * 055 * <p>If {@code nodeU} and {@code nodeV} are not already present in this graph, this method will 056 * silently {@link #addNode(Object) add} {@code nodeU} and {@code nodeV} to the graph. 057 * 058 * @return the value previously associated with the edge connecting {@code nodeU} to {@code 059 * nodeV}, or null if there was no such edge. 060 * @throws IllegalArgumentException if the introduction of the edge would violate {@link 061 * #allowsSelfLoops()} 062 */ 063 @CanIgnoreReturnValue 064 @CheckForNull 065 V putEdgeValue(N nodeU, N nodeV, V value); 066 067 /** 068 * Adds an edge connecting {@code endpoints} if one is not already present, and sets a value for 069 * that edge to {@code value} (overwriting the existing value, if any). 070 * 071 * <p>If the graph is directed, the resultant edge will be directed; otherwise, it will be 072 * undirected. 073 * 074 * <p>If this graph is directed, {@code endpoints} must be ordered. 075 * 076 * <p>Values do not have to be unique. However, values must be non-null. 077 * 078 * <p>If either or both endpoints are not already present in this graph, this method will silently 079 * {@link #addNode(Object) add} each missing endpoint to the graph. 080 * 081 * @return the value previously associated with the edge connecting {@code nodeU} to {@code 082 * nodeV}, or null if there was no such edge. 083 * @throws IllegalArgumentException if the introduction of the edge would violate {@link 084 * #allowsSelfLoops()} 085 * @throws IllegalArgumentException if the endpoints are unordered and the graph is directed 086 * @since 27.1 087 */ 088 @CanIgnoreReturnValue 089 @CheckForNull 090 V putEdgeValue(EndpointPair<N> endpoints, V value); 091 092 /** 093 * Removes {@code node} if it is present; all edges incident to {@code node} will also be removed. 094 * 095 * @return {@code true} if the graph was modified as a result of this call 096 */ 097 @CanIgnoreReturnValue 098 boolean removeNode(N node); 099 100 /** 101 * Removes the edge connecting {@code nodeU} to {@code nodeV}, if it is present. 102 * 103 * @return the value previously associated with the edge connecting {@code nodeU} to {@code 104 * nodeV}, or null if there was no such edge. 105 */ 106 @CanIgnoreReturnValue 107 @CheckForNull 108 V removeEdge(N nodeU, N nodeV); 109 110 /** 111 * Removes the edge connecting {@code endpoints}, if it is present. 112 * 113 * <p>If this graph is directed, {@code endpoints} must be ordered. 114 * 115 * @return the value previously associated with the edge connecting {@code endpoints}, or null if 116 * there was no such edge. 117 * @since 27.1 118 */ 119 @CanIgnoreReturnValue 120 @CheckForNull 121 V removeEdge(EndpointPair<N> endpoints); 122}