EdgeWeights.java

/*
 * Copyright 2012 Odysseus Software GmbH
 *
 * 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 de.odysseus.ithaka.digraph;

/**
 * Edge weights interface.
 * 
 * @param <V> vertex type
 */
public interface EdgeWeights<V> {
	/**
	 * Unit edge weights.
	 */
	public static final EdgeWeights<Object> UNIT_WEIGHTS = new EdgeWeights<Object>() {
		/**
		 * @param source
		 * @param target
		 * @return 1
		 */
		@Override
		public Integer get(Object source, Object target) {
			return Integer.valueOf(1);
		}
	};
	
	/**
	 * Get edge weight
	 * @param source source vertex
	 * @param target target vertex
	 * @return weight for edge starting at <code>source</code> and ending at <code>target</code>
	 */
	public Integer get(V source, V target);
}