package org.apache.helix;

/*
 * 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.
 */

import java.util.List;

/**
 * Constructs ZNRecords from collections of ZNRecords
 */
public class ZNRecordAssembler {
  /**
   * Merge a list of ZNRecords into a single ZNRecord
   * @param records
   * @return {@link ZNRecord}
   */
  public ZNRecord assemble(List<ZNRecord> records) {
    ZNRecord assembledRecord = null;
    if (records != null && records.size() > 0) {
      for (ZNRecord record : records) {
        if (record == null) {
          continue;
        }

        if (assembledRecord == null) {
          assembledRecord = new ZNRecord(record.getId());
        }

        assembledRecord.merge(record);
      }
    }
    return assembledRecord;
  }

}