content: /*
   * 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.ambari.server.orm.helpers;
  
  import java.util.Collection;
  
  import com.google.common.collect.Iterables;
  
  public class SQLOperations {
    public interface BatchOperation<T> {
      /**
       * @param chunk        portion of total batch
       * @param currentBatch current batch number
       * @param totalBatches total batches
       * @param totalSize    total size of the batch
       * @return number of processed items
       */
      int chunk(Collection<T> chunk, int currentBatch, int totalBatches, int totalSize);
    }
  
    /**
     * Split the collection to the batches
     *
     * @param collection collection with values to be splitted
     * @param batchSize  size of the one split
     * @param callback   logic to process one split
     * @return Total number of processed items in collection
     */
    public static <T> int batch(Collection<T> collection, int batchSize, BatchOperation<T> callback) {
      if (collection == null || collection.isEmpty() || batchSize == 0) {
        return 0;
      }
      int totalSize = collection.size();
      int totalChunks = (int) Math.ceil((float) totalSize / batchSize);
      int currentChunk = 0;
      int resultSum = 0;
  
      for (Collection<T> chunk : Iterables.partition(collection, batchSize)) {
        currentChunk += 1;
        resultSum += callback.chunk(chunk, currentChunk, totalChunks, totalSize);
      }
      return resultSum;
    }
  }
  