/*
    * 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.io.hcatalog;
  
  import com.google.common.base.Splitter;
  import com.google.common.collect.Lists;
  import com.google.common.collect.Maps;
  
  import java.util.List;
  import java.util.Map;
  
  /**
   * Utilities and helpers for working with Hive tables.
   */
  public class HiveUtils {
    // TODO use Hive util class if this is already provided by it
  
    /**
     * Private constructor for helper class.
     */
    private HiveUtils() {
      // Do nothing.
    }
  
    /**
    * @param outputTablePartitionString table partition string
    * @return Map
    */
    public static Map<String, String> parsePartitionValues(
        String outputTablePartitionString) {
      if (outputTablePartitionString == null) {
        return null;
      }
      Splitter commaSplitter = Splitter.on(',').omitEmptyStrings().trimResults();
      Splitter equalSplitter = Splitter.on('=').omitEmptyStrings().trimResults();
      Map<String, String> partitionValues = Maps.newHashMap();
      for (String keyValStr : commaSplitter.split(outputTablePartitionString)) {
        List<String> keyVal = Lists.newArrayList(equalSplitter.split(keyValStr));
        if (keyVal.size() != 2) {
          throw new IllegalArgumentException(
              "Unrecognized partition value format: " +
              outputTablePartitionString);
        }
        partitionValues.put(keyVal.get(0), keyVal.get(1));
      }
      return partitionValues;
    }
  }