com.google.common.graph.GraphConnections Maven / Gradle / Ivy
/*
* Copyright (C) 2016 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.errorprone.annotations.CanIgnoreReturnValue;
import java.util.Set;
import org.checkerframework.checker.nullness.compatqual.NullableDecl;
/**
* An interface for representing and manipulating an origin node's adjacent nodes and edge values in
* a {@link Graph}.
*
* @author James Sexton
* @param Node parameter type
* @param Value parameter type
*/
interface GraphConnections {
Set adjacentNodes();
Set predecessors();
Set successors();
/**
* Returns the value associated with the edge connecting the origin node to {@code node}, or null
* if there is no such edge.
*/
@NullableDecl
V value(N node);
/** Remove {@code node} from the set of predecessors. */
void removePredecessor(N node);
/**
* Remove {@code node} from the set of successors. Returns the value previously associated with
* the edge connecting the two nodes.
*/
@CanIgnoreReturnValue
V removeSuccessor(N node);
/**
* Add {@code node} as a predecessor to the origin node. In the case of an undirected graph, it
* also becomes a successor. Associates {@code value} with the edge connecting the two nodes.
*/
void addPredecessor(N node, V value);
/**
* Add {@code node} as a successor to the origin node. In the case of an undirected graph, it also
* becomes a predecessor. Associates {@code value} with the edge connecting the two nodes. Returns
* the value previously associated with the edge connecting the two nodes.
*/
@CanIgnoreReturnValue
V addSuccessor(N node, V value);
}