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Spring Boot starter for storing data as an entity-subentity hierarchy with a parent-child relationship.

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/*
 * Copyright 2022 Nedra Team
 *
 * 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
 *
 *     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 digital.nedra.commons.starter.dao.domain;

import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import java.util.Map;
import java.util.stream.Collectors;
import lombok.AllArgsConstructor;
import lombok.Data;

/**
 * Helper converting list to map.
 *
 * @param  key
 * @param  value
 */
@Data
@AllArgsConstructor
public class Pair {
  private L leftValue;
  private R rightValue;

  /**
   * Return map from {@link Pair} list.
   *
   * @param list DTO list
   * @param   key
   * @param   value
   * @return map
   */
  public static  Map toMap(List> list) {
    if (list == null) {
      return Collections.emptyMap();
    }
    return list.parallelStream()
        .collect(Collectors.toMap(Pair::getLeftValue, Pair::getRightValue));
  }

  public static  List> toListOfPair(Map map) {
    if (map == null) {
      return Collections.emptyList();
    }
    List> list = new ArrayList<>();
    map.forEach((key, value) -> list.add(new Pair<>(key, value)));
    return list;

  }
}