content: /**
   * Copyright (c) 2019 Siemens AG
   * All rights reserved.
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions are met:
   *
   * 1) Redistributions of source code must retain the above copyright notice, this
   *    list of conditions and the following disclaimer.
   *
   * 2) Redistributions in binary form must reproduce the above copyright notice,
   *    this list of conditions and the following disclaimer in the documentation
   *    and/or other materials provided with the distribution.
   *
   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
   * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
   * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
   * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
   * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
   * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
   * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
   * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
   * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
   */
  package at.ac.tuwien.kr.alpha.core.solver;
  
  import java.util.ArrayList;
  import java.util.Collections;
  import java.util.HashMap;
  import java.util.List;
  import java.util.Map;
  
  import at.ac.tuwien.kr.alpha.api.programs.atoms.Atom;
  
  /**
   * Counts the number of ground atoms stored for each type (i.e., subclass of {@link AbstractAtom}.
   * For every atom, only the counter for one class (the most specific one) is incremented,
   * not the counters for more general classes of which the atom is also an instance.
   */
  public class AtomCounter {
  
  	private final Map<String, Integer> countByType = new HashMap<>();
  
  	public void add(Atom atom) {
  		countByType.compute(atom.getClass().getSimpleName(), (k, v) -> (v == null) ? 1 : v + 1);
  	}
  
  	/**
  	 * @param type the class of atoms to count
  	 * @return the number of atoms of the given type
  	 */
  	public int getNumberOfAtoms(String type) {
  		return countByType.getOrDefault(type, 0);
  	}
  
  	/**
  	 * @return a string giving statistics on numbers of atoms by type
  	 */
  	public String getStatsByType() {
  		List<String> statsList = new ArrayList<>();
  		for (Map.Entry<String, Integer> entry : countByType.entrySet()) {
  			statsList.add(entry.getKey() + ": " + entry.getValue());
  		}
  		Collections.sort(statsList);
  		return String.join(" ", statsList);
  	}
  
  }
  