content: /*
   * Tencent is pleased to support the open source community by making Angel available.
   *
   * Copyright (C) 2017-2018 THL A29 Limited, a Tencent company. All rights reserved.
   *
   * 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
   *
   * https://opensource.org/licenses/Apache-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.tencent.angel.graph.client.psf.summary;
  
  import com.tencent.angel.graph.data.GraphNode;
  import com.tencent.angel.ml.matrix.psf.aggr.enhance.UnaryAggrFunc;
  import com.tencent.angel.ps.storage.vector.ServerLongAnyRow;
  import com.tencent.angel.ps.storage.vector.ServerRow;
  import com.tencent.angel.ps.storage.vector.element.IElement;
  import com.tencent.angel.ps.storage.vector.storage.LongElementStorage;
  import it.unimi.dsi.fastutil.longs.Long2ObjectMap;
  import it.unimi.dsi.fastutil.objects.ObjectIterator;
  
  public class NnzNeighbor extends UnaryAggrFunc {
  
      public NnzNeighbor(int matrixId, int rowId) {
          super(matrixId, rowId);
      }
  
      public NnzNeighbor() {
      }
  
      @Override
      public double mergeInit() {
          return 0;
      }
  
      @Override
      public double mergeOp(double a, double b) {
          return a + b;
      }
  
      @Override
      public double processRow(ServerRow row) {
          LongElementStorage storage = ((ServerLongAnyRow) row).getStorage();
          ObjectIterator<Long2ObjectMap.Entry<IElement>> it = storage.iterator();
          int size = 0;
          while (it.hasNext()) {
              GraphNode node = (GraphNode) (it.next().getValue());
              if (node.getNeighbors() != null) {
                  size++;
              }
          }
          return size;
      }
  }