/*
 * This file is part of ELKI:
 * Environment for Developing KDD-Applications Supported by Index-Structures
 *
 * Copyright (C) 2022
 * ELKI Development Team
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU Affero General Public License for more details.
 *
 * You should have received a copy of the GNU Affero General Public License
 * along with this program. If not, see <http://www.gnu.org/licenses/>.
 */
package elki.parallel.variables;

/**
 * Variable to share between different processors (within one thread only!)
 * 
 * @author Erich Schubert
 * @since 0.7.0
 * 
 * @has - - - SharedObject.Instance
 * 
 * @param <T> Data type
 */
public class SharedObject<T> implements SharedVariable<SharedObject.Instance<T>> {
  @Override
  public Instance<T> instantiate() {
    return new Instance<>();
  }

  /**
   * Instance for a particular thread.
   * 
   * @author Erich Schubert
   * 
   * @param <T> Data type
   */
  public static class Instance<T> implements SharedVariable.Instance<T> {
    /**
     * Cache for last data consumed/produced
     */
    private T data = null;

    @Override
    public T get() {
      return data;
    }

    @Override
    public void set(T data) {
      this.data = data;
    }
  }
}