if (handler != null) {
                        break;
                    }
                }
            }
            if (handler == null) {
                throw new IOException("Unable to find default handler for protocol: " + protocol);
            }
            PROTOCOL_HANDLERS.put(protocol, handler);
            return handler;
        }
    }

    checkNotNull(rowFunction, "rowFunction");
    checkNotNull(columnFunction, "columnFunction");
    checkNotNull(valueFunction, "valueFunction");
    checkNotNull(mergeFunction, "mergeFunction");

    /*
     * No mutable Table exactly matches the insertion order behavior of ImmutableTable.Builder, but
     * the Builder can't efficiently support merging of duplicate values.  Getting around this
     * requires some work.
     */

   *
   * @param <V> the type of the result
   */
  @FunctionalInterface
  public interface ClosingCallable<V extends @Nullable Object> {
    /**
     * Computes a result, or throws an exception if unable to do so.
     *
     * <p>Any objects that are passed to {@link DeferredCloser#eventuallyClose(Object, Executor)
     * closer.eventuallyClose()} will be closed when the {@link ClosingFuture} pipeline is done (but

import java.util.Iterator;
import java.util.LinkedHashMap;
import java.util.Map;
import java.util.Set;
import org.jspecify.annotations.NonNull;
import org.jspecify.annotations.Nullable;

/**
 * A mutable class-to-instance map backed by an arbitrary user-provided map. See also {@link
 * ImmutableClassToInstanceMap}.
 *
 * <p>See the Guava User Guide article on <a href=

   * host specifier is a domain name, the string will be normalized to all lower case. If the
   * specifier was an IPv6 address without brackets, brackets are added so that the result will be
   * usable in the host part of a URI.
   */
  @Override
  public String toString() {
    return canonicalForm;
  }

  /** Creates an empty {@code CompactHashSet} instance. */
  public static <E extends @Nullable Object> CompactHashSet<E> create() {
    return new CompactHashSet<>();
  }

  /**
   * Creates a <i>mutable</i> {@code CompactHashSet} instance containing the elements of the given
   * collection in unspecified order.
   *
   * @param collection the elements that the set should contain

                totalHealthChecks.get(), failedHealthChecks.get(), connectionsRemoved.get(), connectionMetrics.size(),
                healthCheckingEnabled, proactiveHealthCheckEnabled);
    }

    /**
     * Enable or disable health checking
     */
    public void setHealthCheckingEnabled(boolean enabled) {
        this.healthCheckingEnabled = enabled;
        if (enabled) {
            startProactiveHealthChecking();
        } else {

    @SuppressWarnings("EffectivelyPrivate")
    public final void tearDown() throws IOException {
      if (!fileThreadLocal.get().delete()) {
        logger.warning("Unable to delete file: " + fileThreadLocal.get());
      }
      fileThreadLocal.remove();
    }
  }

  private static class FileByteSourceFactory extends FileFactory implements ByteSourceFactory {

    @Override

   * snapshot of the state and therefore it can be used to answer simple queries without needing to
   * grab a lock.
   */
  // @Immutable except that Throwable is mutable (initCause(), setStackTrace(), mutable subclasses).
  private static final class StateSnapshot {
    /**
     * The internal state, which equals external state unless shutdownWhenStartupFinishes is true.
     */
    final State state;

 * Immutable empty instances are returned for collection types; {@code ""} for string; {@code 0} for
 * number types; reasonable default instance for other stateless types. For mutable types, a fresh
 * instance is created each time {@code get()} is called.
 *
 * @author Kevin Bourrillion
 * @author Ben Yu
 * @since 12.0
 */
@GwtIncompatible
@J2ktIncompatible
@NullMarked