/*

  * 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.giraph.block_app.test_setup.graphs;

 import org.apache.giraph.block_app.test_setup.NumericTestGraph;

 import org.apache.giraph.block_app.test_setup.TestGraphModifier;

 import org.apache.giraph.function.Supplier;

 import org.apache.hadoop.io.Writable;

 import org.apache.hadoop.io.WritableComparable;

 /**

  * Create a network that looks like:

  *   1      5

  *  / \    / \    6

  * 0---2  3---4

  *

  * where 6 is disconnected from the rest of the network.

  *

  * @param <I> Vertex id type

  * @param <V> Vertex value type

  * @param <E> Edge value type

  */

 public class Small2GraphInit<I extends WritableComparable,

     V extends Writable, E extends Writable>

     implements TestGraphModifier<I, V, E> {

   private final Supplier<E> edgeSupplier;

   public Small2GraphInit() {

     this(null);

   }

   public Small2GraphInit(Supplier<E> edgeSupplier) {

     this.edgeSupplier = edgeSupplier;

   }

   @Override

   public void modifyGraph(NumericTestGraph<I, V, E> graph) {

     graph.addSymmetricEdge(0, 1, createEdgeValue());

     graph.addSymmetricEdge(0, 2, createEdgeValue());

     graph.addSymmetricEdge(1, 2, createEdgeValue());

     graph.addSymmetricEdge(3, 4, createEdgeValue());

     graph.addSymmetricEdge(3, 5, createEdgeValue());

     graph.addSymmetricEdge(4, 5, createEdgeValue());

     graph.addVertex(6);

   }

   private E createEdgeValue() {

     return edgeSupplier != null ? edgeSupplier.get() : null;

   }

 }