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/*
 * Copyright (C) 2014 The Guava 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
 *
 * http://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 com.google.common.graph;

import com.google.common.annotations.Beta;
import com.google.errorprone.annotations.CanIgnoreReturnValue;


A subinterface of Network which adds mutation methods. When mutation is not required, users should prefer the Network interface. 
Author:James Sexton, Joshua O'Madadhain
Type parameters:
  • <N> – Node parameter type
  • <E> – Edge parameter type
Since:20.0
/**
 * A subinterface of {@link Network} which adds mutation methods. When mutation is not required,
 * users should prefer the {@link Network} interface.
 *
 * @author James Sexton
 * @author Joshua O'Madadhain
 * @param <N> Node parameter type
 * @param <E> Edge parameter type
 * @since 20.0
 */
@Beta
public interface MutableNetwork<N, E> extends Network<N, E> {

  
Adds node if it is not already present. 
Nodes must be unique, just as Map keys must be. They must also be non-null. 
Returns:true if the network was modified as a result of this call
/**
   * Adds {@code node} if it is not already present.
   *
   * <p><b>Nodes must be unique</b>, just as {@code Map} keys must be. They must also be non-null.
   *
   * @return {@code true} if the network was modified as a result of this call
   */
  @CanIgnoreReturnValue
  boolean addNode(N node);

  
Adds edge connecting nodeU to nodeV. 
If the graph is directed, edge will be directed in this graph; otherwise, it will be undirected. 
edge must be unique to this graph, just as a Map key must be. It must also be non-null. 
If nodeU and nodeV are not already present in this graph, this method will silently add nodeU and nodeV to the graph. 
If edge already connects nodeU to nodeV (in the specified order if this network Network.isDirected(), else in any order), then this method will have no effect. 
Throws:
Returns:true if the network was modified as a result of this call
/**
   * Adds {@code edge} connecting {@code nodeU} to {@code nodeV}.
   *
   * <p>If the graph is directed, {@code edge} will be directed in this graph; otherwise, it will be
   * undirected.
   *
   * <p><b>{@code edge} must be unique to this graph</b>, just as a {@code Map} key must be. It must
   * also be non-null.
   *
   * <p>If {@code nodeU} and {@code nodeV} are not already present in this graph, this method will
   * silently {@link #addNode(Object) add} {@code nodeU} and {@code nodeV} to the graph.
   *
   * <p>If {@code edge} already connects {@code nodeU} to {@code nodeV} (in the specified order if
   * this network {@link #isDirected()}, else in any order), then this method will have no effect.
   *
   * @return {@code true} if the network was modified as a result of this call
   * @throws IllegalArgumentException if {@code edge} already exists in the graph and does not
   *     connect {@code nodeU} to {@code nodeV}
   * @throws IllegalArgumentException if the introduction of the edge would violate {@link
   *     #allowsParallelEdges()} or {@link #allowsSelfLoops()}
   */
  @CanIgnoreReturnValue
  boolean addEdge(N nodeU, N nodeV, E edge);

  
Adds edge connecting endpoints. In an undirected network, edge will also connect nodeV to nodeU. 
If this graph is directed, edge will be directed in this graph; if it is undirected, edge will be undirected in this graph. 
If this graph is directed, endpoints must be ordered. 
edge must be unique to this graph, just as a Map key must be. It must also be non-null. 
If either or both endpoints are not already present in this graph, this method will silently add each missing endpoint to the graph. 
If edge already connects an endpoint pair equal to endpoints, then this method will have no effect. 
Throws:
Returns:true if the network was modified as a result of this call
Since:27.1
/**
   * Adds {@code edge} connecting {@code endpoints}. In an undirected network, {@code edge} will
   * also connect {@code nodeV} to {@code nodeU}.
   *
   * <p>If this graph is directed, {@code edge} will be directed in this graph; if it is undirected,
   * {@code edge} will be undirected in this graph.
   *
   * <p>If this graph is directed, {@code endpoints} must be ordered.
   *
   * <p><b>{@code edge} must be unique to this graph</b>, just as a {@code Map} key must be. It must
   * also be non-null.
   *
   * <p>If either or both endpoints are not already present in this graph, this method will silently
   * {@link #addNode(Object) add} each missing endpoint to the graph.
   *
   * <p>If {@code edge} already connects an endpoint pair equal to {@code endpoints}, then this
   * method will have no effect.
   *
   * @return {@code true} if the network was modified as a result of this call
   * @throws IllegalArgumentException if {@code edge} already exists in the graph and connects some
   *     other endpoint pair that is not equal to {@code endpoints}
   * @throws IllegalArgumentException if the introduction of the edge would violate {@link
   *     #allowsParallelEdges()} or {@link #allowsSelfLoops()}
   * @throws IllegalArgumentException if the endpoints are unordered and the graph is directed
   * @since 27.1
   */
  @CanIgnoreReturnValue
  boolean addEdge(EndpointPair<N> endpoints, E edge);

  
Removes node if it is present; all edges incident to node will also be removed. 
Returns:true if the network was modified as a result of this call
/**
   * Removes {@code node} if it is present; all edges incident to {@code node} will also be removed.
   *
   * @return {@code true} if the network was modified as a result of this call
   */
  @CanIgnoreReturnValue
  boolean removeNode(N node);

  
Removes edge from this network, if it is present. 
Returns:true if the network was modified as a result of this call
/**
   * Removes {@code edge} from this network, if it is present.
   *
   * @return {@code true} if the network was modified as a result of this call
   */
  @CanIgnoreReturnValue
  boolean removeEdge(E edge);
}