* "https://github.com/google/guava/wiki/RangesExplained#discrete-domains">{@code
 * DiscreteDomain}</a>.
 *
 * @author Kevin Bourrillion
 * @since 10.0
 */
@SuppressWarnings("rawtypes") // https://github.com/google/guava/issues/989
@GwtCompatible
public abstract class DiscreteDomain<C extends Comparable> {

  /**
   * Returns the discrete domain for values of type {@code Integer}.
   *

  abstract Cut<C> withUpperBoundType(BoundType boundType, DiscreteDomain<C> domain);

  abstract void describeAsLowerBound(StringBuilder sb);

  abstract void describeAsUpperBound(StringBuilder sb);

  abstract @Nullable C leastValueAbove(DiscreteDomain<C> domain);

  abstract @Nullable C greatestValueBelow(DiscreteDomain<C> domain);

  /*

   * @since 23.0
   */
  public static ContiguousSet<Long> closedOpen(long lower, long upper) {
    return create(Range.closedOpen(lower, upper), DiscreteDomain.longs());
  }

  final DiscreteDomain<C> domain;

  ContiguousSet(DiscreteDomain<C> domain) {
    super(Ordering.natural());
    this.domain = domain;
  }

  @Override
  public ContiguousSet<C> headSet(C toElement) {

  abstract Cut<C> withUpperBoundType(BoundType boundType, DiscreteDomain<C> domain);

  abstract void describeAsLowerBound(StringBuilder sb);

  abstract void describeAsUpperBound(StringBuilder sb);

  abstract @Nullable C leastValueAbove(DiscreteDomain<C> domain);

  abstract @Nullable C greatestValueBelow(DiscreteDomain<C> domain);

  /*

      for (Object o : elements) {
        Integer i = (Integer) o;
        builder.add(Range.singleton(i));
      }
      return builder.build().asSet(DiscreteDomain.integers());
    }
  }

  @AndroidIncompatible // test-suite builders
  static final class ImmutableRangeSetBigIntegerAsSetGenerator
      implements TestSetGenerator<BigInteger> {
    @Override

   * @since 23.0
   */
  public static ContiguousSet<Long> closedOpen(long lower, long upper) {
    return create(Range.closedOpen(lower, upper), DiscreteDomain.longs());
  }

  final DiscreteDomain<C> domain;

  ContiguousSet(DiscreteDomain<C> domain) {
    super(Ordering.natural());
    this.domain = domain;
  }

  @Override
  public ContiguousSet<C> headSet(C toElement) {

import com.google.common.annotations.GwtCompatible;
import com.google.common.annotations.GwtIncompatible;
import com.google.common.collect.ContiguousSet;
import com.google.common.collect.DiscreteDomain;
import com.google.common.collect.ImmutableSet;
import com.google.common.collect.ImmutableSortedSet;
import com.google.common.collect.Lists;
import com.google.common.collect.Ordering;

      throw new IllegalArgumentException(
          "Neither the DiscreteDomain nor this range set are bounded below");
    } else if (!span.hasUpperBound()) {
      try {
        domain.maxValue();
      } catch (NoSuchElementException e) {
        throw new IllegalArgumentException(
            "Neither the DiscreteDomain nor this range set are bounded above");
      }
    }

import org.jspecify.annotations.NullUnmarked;

/**
 * @author Gregory Kick
 */
@GwtCompatible
@NullUnmarked
public class ContiguousSetTest extends TestCase {
  private static final DiscreteDomain<Integer> NOT_EQUAL_TO_INTEGERS =
      new DiscreteDomain<Integer>() {
        @Override
        public Integer next(Integer value) {
          return integers().next(value);
        }

        @Override

import org.jspecify.annotations.NullUnmarked;

/**
 * @author Gregory Kick
 */
@GwtCompatible
@NullUnmarked
public class ContiguousSetTest extends TestCase {
  private static final DiscreteDomain<Integer> NOT_EQUAL_TO_INTEGERS =
      new DiscreteDomain<Integer>() {
        @Override
        public Integer next(Integer value) {
          return integers().next(value);
        }

        @Override