Builder<String, Integer> builder = new Builder<>();
    assertThrows(
        NullPointerException.class,
        () -> builder.putAll(Collections.<String, Integer>singletonMap("one", null)));
  }

  @SuppressWarnings("AlwaysThrows")
  public void testPuttingTheSameKeyTwiceThrowsOnBuild() {
    Builder<String, Integer> builder =
        new Builder<String, Integer>()
            .put("one", 1)

        rowFunction, columnFunction, valueFunction, mergeFunction);
  }

  /**
   * Returns an empty immutable table.
   *
   * <p><b>Performance note:</b> the instance returned is a singleton.
   */
  @SuppressWarnings("unchecked")
  public static <R, C, V> ImmutableTable<R, C, V> of() {
    return (ImmutableTable<R, C, V>) SparseImmutableTable.EMPTY;
  }

  /** Returns an immutable table containing a single cell. */

 */
@GwtCompatible
@Ignore("test runners must not instantiate and run this directly, only via suites we build")
// @Ignore affects the Android test runner, which respects JUnit 4 annotations on JUnit 3 tests.
@SuppressWarnings("JUnit4ClassUsedInJUnit3")
@NullMarked
public class ConcurrentMapPutIfAbsentTester<K, V> extends AbstractMapTester<K, V> {
  @Override
  protected ConcurrentMap<K, V> getMap() {

        Proxy.newProxyInstance(
            interfaceClasses.iterator().next().getClassLoader(),
            interfaceClasses.toArray(new Class<?>[interfaceClasses.size()]),
            new DummyHandler(interfaceType));
    @SuppressWarnings("unchecked") // interfaceType is T
    T result = (T) dummy;
    return result;
  }

  /** Returns the dummy return value for {@code returnType}. */

    } else {
      for (int remaining = b.remaining(); remaining > 0; remaining--) {
        update(b.get());
      }
    }
  }

  /** Updates the sink with the given number of bytes from the buffer. */
  @SuppressWarnings("ByteBufferBackingArray") // We created the array with ByteBuffer.allocate().
  @CanIgnoreReturnValue
  private Hasher update(ByteBuffer scratch, int bytes) {
    try {
      update(scratch.array(), 0, bytes);

         * size.
         */
        return HashCode.fromInt((int) value);
      } else {
        return HashCode.fromLong(value);
      }
    }
  }

  @J2ObjCIncompatible
  @SuppressWarnings("unused")
  private static final class ChecksumMethodHandles {
    private static final @Nullable MethodHandle UPDATE_BB = updateByteBuffer();

import org.jspecify.annotations.Nullable;

/**
 * Static utility methods pertaining to object arrays.
 *
 * @author Kevin Bourrillion
 * @since 2.0
 */
@GwtCompatible
@SuppressWarnings("AvoidObjectArrays")
public final class ObjectArrays {

  private ObjectArrays() {}

  /**
   * Returns a new array of the given length with the specified component type.
   *

import java.util.LinkedHashSet;
import java.util.Set;
import java.util.SortedSet;

/**
 * Optional features of classes derived from {@code Collection}.
 *
 * @author George van den Driessche
 */
@SuppressWarnings("rawtypes") // maybe avoidable if we rework the whole package?
@GwtCompatible
public enum CollectionFeature implements Feature<Collection> {
  /**

            .withFeatures(CollectionSize.ANY, CollectionFeature.ALLOWS_NULL_VALUES)
            .createTestSuite());

    return suite;
  }

  @SuppressWarnings({"rawtypes", "unchecked"})
  public void testForwarding() {
    new ForwardingWrapperTester()
        .testForwarding(
            Set.class,
            new Function<Set, Set>() {
              @Override

    CHILE,
    JAPAN,
    SWITZERLAND,
    UK
  }

  @AndroidIncompatible // test-suite builders
  public static final class EnumBiMapGenerator implements TestBiMapGenerator<Country, Currency> {
    @SuppressWarnings("unchecked")
    @Override
    public BiMap<Country, Currency> create(Object... entries) {
      BiMap<Country, Currency> result = EnumBiMap.create(Country.class, Currency.class);
      for (Object object : entries) {