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