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.psf.hyperanf;
  
  import com.tencent.angel.ml.matrix.psf.aggr.enhance.ScalarPartitionAggrResult;
  import com.tencent.angel.ml.matrix.psf.get.base.GetFunc;
  import com.tencent.angel.ml.matrix.psf.get.base.GetParam;
  import com.tencent.angel.ml.matrix.psf.get.base.GetResult;
  import com.tencent.angel.ml.matrix.psf.get.base.PartitionGetParam;
  import com.tencent.angel.ml.matrix.psf.get.base.PartitionGetResult;
  import com.tencent.angel.ps.storage.vector.ServerLongAnyRow;
  import java.util.List;
  
  public class NumNodes extends GetFunc {
  
    public NumNodes(int matrixId) {
      this(new GetParam(matrixId));
    }
  
    public NumNodes(GetParam param) {
      super(param);
    }
  
    public NumNodes() {
      super(null);
    }
  
    @Override
    public PartitionGetResult partitionGet(PartitionGetParam partParam) {
      ServerLongAnyRow row = (ServerLongAnyRow) psContext.getMatrixStorageManager()
              .getRow(partParam.getPartKey(), 0);
      return new ScalarPartitionAggrResult(row.size());
    }
  
    @Override
    public GetResult merge(List<PartitionGetResult> partResults) {
      long numNodes = 0;
      for (PartitionGetResult result : partResults) {
        if (result instanceof ScalarPartitionAggrResult) {
          long value = (long) ((ScalarPartitionAggrResult) result).result;
          numNodes += value;
        }
      }
      return new NumNodesResult(numNodes);
    }
  }
  