import java.util.NoSuchElementException;
import java.util.stream.Stream;
import junit.framework.TestCase;
import org.jspecify.annotations.NullMarked;
import org.jspecify.annotations.Nullable;

/**
 * Tests for {@code MoreCollectors}.
 *
 * @author Louis Wasserman
 */
@GwtCompatible
@NullMarked
public class MoreCollectorsTest extends TestCase {
  public void testToOptionalEmpty() {

    // These two fields are volatile because their values will be accessed from multiple threads.
    private volatile @Nullable Cancellable runningTask;
    private volatile @Nullable ScheduledExecutorService executorService;

    // This lock protects the task so we can ensure that none of the template methods (startUp,

 */
@Experimental
@Immutable
@Provider
public interface Node {

    /**
     * @return artifact for this node
     */
    @Nullable
    Artifact getArtifact();

    /**
     * @return dependency for this node
     */
    @Nullable
    Dependency getDependency();

    /**
     * Gets the child nodes of this node.
     *
     * @return the child nodes of this node, never {@code null}
     */

import java.util.concurrent.CountDownLatch;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.ExecutorService;
import org.jspecify.annotations.NullUnmarked;
import org.jspecify.annotations.Nullable;

/**
 * Used to test listenable future implementations.
 *
 * @author Sven Mawson
 */
@NullUnmarked
@GwtIncompatible
@J2ktIncompatible
public class ListenableFutureTester {

  private static final class NewExecutionListQueue {
    static final Logger log = Logger.getLogger(NewExecutionListQueue.class.getName());

    @GuardedBy("this")
    private @Nullable RunnableExecutorPair head;

    @GuardedBy("this")
    private @Nullable RunnableExecutorPair tail;

    @GuardedBy("this")
    private boolean executed;

    void add(Runnable runnable, Executor executor) {

 * limitations under the License.
 */

package com.google.common.graph;

import com.google.common.collect.ImmutableSet;
import java.util.AbstractSet;
import java.util.Set;
import org.jspecify.annotations.Nullable;

/**
 * Abstract base class for an incident edges set that allows different implementations of {@link
 * AbstractSet#iterator()}.
 */
abstract class IncidentEdgeSet<N> extends AbstractSet<EndpointPair<N>> {

import com.google.errorprone.annotations.CanIgnoreReturnValue;
import java.util.concurrent.Callable;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.TimeUnit;
import org.jspecify.annotations.Nullable;

/**
 * A TimeLimiter implementation which actually does not attempt to limit time at all. This may be
 * desirable to use in some unit tests. More importantly, attempting to debug a call which is

import java.util.concurrent.atomic.AtomicInteger;
import junit.framework.Test;
import junit.framework.TestCase;
import junit.framework.TestSuite;
import org.jspecify.annotations.NullMarked;
import org.jspecify.annotations.Nullable;

/**
 * Unit test for {@link AbstractMultiset}.
 *
 * @author Kevin Bourrillion
 * @author Louis Wasserman
 */
@SuppressWarnings("serial") // No serialization is used in this test
@GwtCompatible

 * limitations under the License.
 */

package com.google.common.collect;

import com.google.common.annotations.GwtIncompatible;
import org.jspecify.annotations.Nullable;

/**
 * A skeletal implementation of {@code RangeSet}.
 *
 * @author Louis Wasserman
 */
@SuppressWarnings("rawtypes") // https://github.com/google/guava/issues/989
@GwtIncompatible

 * specific language governing permissions and limitations
 * under the License.
 */
package org.apache.maven.cli.transfer;

import java.io.File;

import org.apache.maven.api.annotations.Nullable;
import org.eclipse.aether.transfer.TransferResource;

/**
 * Immutable identifier of a {@link TransferResource}.