content: /**
   * Copyright 2020 Alibaba Group Holding Limited.
   *
   * <p>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
   *
   * <p>http://www.apache.org/licenses/LICENSE-2.0
   *
   * <p>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.alibaba.graphscope.groot.dataload.databuild;
  
  import com.alibaba.graphscope.groot.common.util.PartitionUtils;
  
  import org.apache.hadoop.io.BytesWritable;
  import org.apache.hadoop.mapreduce.Partitioner;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  import java.nio.ByteBuffer;
  
  public class DataBuildPartitioner extends Partitioner<BytesWritable, BytesWritable> {
  
      private static final Logger logger = LoggerFactory.getLogger(DataBuildPartitioner.class);
  
      @Override
      public int getPartition(BytesWritable key, BytesWritable value, int numPartitions) {
          byte[] keyBytes = key.getBytes();
          ByteBuffer keyBuf = ByteBuffer.wrap(keyBytes);
          // for edge, its key.getLength() > 24
          long partitionKey = keyBuf.getLong(8);
          return PartitionUtils.getPartitionIdFromKey(partitionKey, numPartitions);
      }
  }
  