Vector cost proposed to TST on 2016-07-13
First part implemented: weight interface introduced and integrated, default weight implementation added.
Change-Id: Ia46f1b44139069aa171a3c13faf168351bd7cc56
diff --git a/utils/misc/src/main/java/org/onlab/graph/DefaultEdgeWeigher.java b/utils/misc/src/main/java/org/onlab/graph/DefaultEdgeWeigher.java
new file mode 100644
index 0000000..e280391
--- /dev/null
+++ b/utils/misc/src/main/java/org/onlab/graph/DefaultEdgeWeigher.java
@@ -0,0 +1,53 @@
+/*
+ * Copyright 2016-present Open Networking Laboratory
+ *
+ * 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 org.onlab.graph;
+
+/**
+ * Default weigher returns identical weight for every graph edge. Basically it
+ * is a hop count weigher.
+ * Produces weights of {@link ScalarWeight} type.
+ *
+ * @param <V> vertex type
+ * @param <E> edge type
+ */
+public class DefaultEdgeWeigher<V extends Vertex, E extends Edge<V>>
+ implements EdgeWeigher<V, E> {
+
+ /**
+ * Common weight value for any link.
+ */
+ protected static final double HOP_WEIGHT_VALUE = 1;
+ /**
+ * Weight value for null path (without links).
+ */
+ protected static final double NULL_WEIGHT_VALUE = 0;
+
+ @Override
+ public Weight weight(E edge) {
+ return new ScalarWeight(HOP_WEIGHT_VALUE);
+ }
+
+ @Override
+ public Weight getInitialWeight() {
+ return new ScalarWeight(NULL_WEIGHT_VALUE);
+ }
+
+ @Override
+ public Weight getNonViableWeight() {
+ return ScalarWeight.NON_VIABLE_WEIGHT;
+ }
+}