/**
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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 org.apache.tajo.util.graph;
import org.apache.tajo.annotation.Nullable;
import java.util.Collection;
/**
* This is the topmost graph interface. It only provides essential graph features.
* @param <V> Vertex class
* @param <E> Edge Class
*/
public interface Graph<V, E> {
int getVertexSize();
int getEdgeNum();
void addEdge(V tail, V head, E edge);
void removeEdge(V tail, V head);
boolean hasEdge(V tail, V head);
@Nullable E getEdge(V tail, V head);
Collection<E> getEdgesAll();
}