com.google.common.graph.UndirectedGraphConnections Maven / Gradle / Ivy
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This artifact provides a single jar that contains all classes required to use remote EJB and JMS, including
all dependencies. It is intended for use by those not using maven, maven users should just import the EJB and
JMS BOM's instead (shaded JAR's cause lots of problems with maven, as it is very easy to inadvertently end up
with different versions on classes on the class path).
/*
* 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 static com.google.common.base.Preconditions.checkNotNull;
import static com.google.common.graph.GraphConstants.INNER_CAPACITY;
import static com.google.common.graph.GraphConstants.INNER_LOAD_FACTOR;
import com.google.common.collect.ImmutableMap;
import com.google.common.collect.Iterators;
import java.util.Collections;
import java.util.HashMap;
import java.util.Iterator;
import java.util.LinkedHashMap;
import java.util.Map;
import java.util.Set;
import javax.annotation.CheckForNull;
/**
* An implementation of {@link GraphConnections} for undirected graphs.
*
* @author James Sexton
* @param Node parameter type
* @param Value parameter type
*/
@ElementTypesAreNonnullByDefault
final class UndirectedGraphConnections implements GraphConnections {
private final Map adjacentNodeValues;
private UndirectedGraphConnections(Map adjacentNodeValues) {
this.adjacentNodeValues = checkNotNull(adjacentNodeValues);
}
static UndirectedGraphConnections of(ElementOrder incidentEdgeOrder) {
switch (incidentEdgeOrder.type()) {
case UNORDERED:
return new UndirectedGraphConnections<>(
new HashMap(INNER_CAPACITY, INNER_LOAD_FACTOR));
case STABLE:
return new UndirectedGraphConnections<>(
new LinkedHashMap(INNER_CAPACITY, INNER_LOAD_FACTOR));
default:
throw new AssertionError(incidentEdgeOrder.type());
}
}
static UndirectedGraphConnections ofImmutable(Map adjacentNodeValues) {
return new UndirectedGraphConnections<>(ImmutableMap.copyOf(adjacentNodeValues));
}
@Override
public Set adjacentNodes() {
return Collections.unmodifiableSet(adjacentNodeValues.keySet());
}
@Override
public Set predecessors() {
return adjacentNodes();
}
@Override
public Set successors() {
return adjacentNodes();
}
@Override
public Iterator> incidentEdgeIterator(N thisNode) {
return Iterators.transform(
adjacentNodeValues.keySet().iterator(),
(N incidentNode) -> EndpointPair.unordered(thisNode, incidentNode));
}
@Override
@CheckForNull
public V value(N node) {
return adjacentNodeValues.get(node);
}
@Override
public void removePredecessor(N node) {
@SuppressWarnings("unused")
V unused = removeSuccessor(node);
}
@Override
@CheckForNull
public V removeSuccessor(N node) {
return adjacentNodeValues.remove(node);
}
@Override
public void addPredecessor(N node, V value) {
@SuppressWarnings("unused")
V unused = addSuccessor(node, value);
}
@Override
@CheckForNull
public V addSuccessor(N node, V value) {
return adjacentNodeValues.put(node, value);
}
}