//                                                                           =========
    private static final FileConfigDbm _instance = new FileConfigDbm();

    private FileConfigDbm() {
    }

    public static FileConfigDbm getInstance() {
        return _instance;
    }

    // ===================================================================================

 * to implement the related methods as well. Finally, two collection views are provided: {@link
 * #elementSet} contains the distinct elements of the multiset "with duplicates collapsed", and
 * {@link #entrySet} is similar but contains {@link Entry Multiset.Entry} instances, each providing
 * both a distinct element and the count of that element.
 *
 * <p>In addition to these required methods, implementations of {@code Multiset} are expected to

        assertTrue(Modifier.isPrivate(constructor.getModifiers()), "Constructor should be private");

        // Force accessibility and create instance to achieve coverage
        constructor.setAccessible(true);
        assertNotNull(constructor.newInstance(), "Should be able to create instance via reflection");
    }

    @Nested
    @DisplayName("Header Constants")
    class HeaderConstants {

        @Test

   * instance.
   */
  private final Map<Type, Integer> emptyInstanceGenerated = new HashMap<>();

  final <T> void addSampleInstances(Class<T> type, Iterable<? extends T> instances) {
    sampleInstances.putAll(checkNotNull(type), checkNotNull(instances));
  }

  /**
   * Returns a fresh instance for {@code type} if possible. The returned instance could be:
   *
   * <ul>

 * to implement the related methods as well. Finally, two collection views are provided: {@link
 * #elementSet} contains the distinct elements of the multiset "with duplicates collapsed", and
 * {@link #entrySet} is similar but contains {@link Entry Multiset.Entry} instances, each providing
 * both a distinct element and the count of that element.
 *
 * <p>In addition to these required methods, implementations of {@code Multiset} are expected to

        }
      };

  enum NullListener implements RemovalListener<Object, Object> {
    INSTANCE;

    @Override
    public void onRemoval(RemovalNotification<Object, Object> notification) {}
  }

  enum OneWeigher implements Weigher<Object, Object> {
    INSTANCE;

    @Override
    public int weigh(Object key, Object value) {
      return 1;
    }
  }

   * actual {@code y} values of the data and the values predicted by the fit for the {@code x}
   * values (i.e. it is the square root of the mean of the squares of the vertical distances between
   * the data points and the best fit line). For this fit, this error is a fraction {@code sqrt(1 -
   * R*R)} of the population standard deviation of {@code y}, where {@code R} is the Pearson's

    //                                                                           =========
    private static final WebConfigDbm _instance = new WebConfigDbm();

    private WebConfigDbm() {
    }

    public static WebConfigDbm getInstance() {
        return _instance;
    }

    // ===================================================================================

    //                                                                           =========
    private static final SearchLogDbm _instance = new SearchLogDbm();

    private SearchLogDbm() {
    }

    public static SearchLogDbm getInstance() {
        return _instance;
    }

    // ===================================================================================

import java.util.ConcurrentModificationException;
import java.util.Iterator;
import java.util.NoSuchElementException;
import org.jspecify.annotations.Nullable;

/**
 * Basic implementation of {@code Multiset<E>} backed by an instance of {@code
 * ObjectCountHashMap<E>}.
 *
 * <p>For serialization to work, the subclass must specify explicit {@code readObject} and {@code
 * writeObject} methods.
 *
 * @author Kevin Bourrillion
 */