private static final class NonSerializableMemoizingSupplier<T extends @Nullable Object>
      implements Supplier<T> {
    private final Object lock = new Object();

    @SuppressWarnings("UnnecessaryLambda") // Must be a fixed singleton object
    private static final Supplier<@Nullable Void> SUCCESSFULLY_COMPUTED =
        () -> {
          throw new IllegalStateException(); // Should never get called.
        };

  companion object {
    /** Empty headers. */
    @JvmField
    val EMPTY = Headers(emptyArray())

    /**
     * Returns headers for the alternating header names and values. There must be an even number of
     * arguments, and they must alternate between header names and values.
     */
    @JvmStatic
    @JvmName("of")
    fun headersOf(vararg namesAndValues: String): Headers = commonHeadersOf(*namesAndValues)

          information.

       3. If requested by the Licensor, You must remove any of the
          information required by Section 3(a)(1)(A) to the extent
          reasonably practicable.

       4. If You Share Adapted Material You produce, the Adapter's
          License You apply must not prevent recipients of the Adapted
          Material from complying with this Public License.

import org.junit.Ignore;

/**
 * Tester for the {@code containsKey} methods of {@code Multimap} and its {@code asMap()} view.
 *
 * @author Louis Wasserman
 */
@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")

import java.util.Iterator;
import java.util.Map.Entry;
import org.junit.Ignore;

/**
 * Tester for {@code Multimap.keySet}.
 *
 * @author Louis Wasserman
 */
@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")

 * method) of a collection. Can't be invoked directly; please see {@link
 * com.google.common.collect.testing.CollectionTestSuiteBuilder}.
 *
 * @author Chris Povirk
 */
@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")

        requireNonNull(pluginBindings);
        final int len = pluginBindings.length;
        if (len < 2 || len % 2 != 0) {
            throw new IllegalArgumentException("Plugin bindings must have more than 0, even count of elements");
        }

        HashMap<String, LifecyclePhase> lifecyclePhaseBindings = new HashMap<>(len / 2);
        for (int i = 0; i < len; i = i + 2) {

 * directly; please see {@link com.google.common.collect.testing.MapTestSuiteBuilder}.
 *
 * @author George van den Driessche
 * @author Chris Povirk
 */
@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")

import java.lang.reflect.Method;
import java.util.Collection;
import org.junit.Ignore;

/**
 * Tests {@link java.util.Set#hashCode}.
 *
 * @author George van den Driessche
 */
@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")

import org.jspecify.annotations.Nullable;
import org.junit.Ignore;

/**
 * Base class for list testers.
 *
 * @author George van den Driessche
 */
@GwtCompatible
@NullMarked
@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")