import java.lang.ref.WeakReference;
import java.util.WeakHashMap;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.atomic.AtomicBoolean;
import junit.framework.TestCase;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * Tests for {@link GcFinalization}.
 *
 * @author Martin Buchholz
 * @author mike nonemacher
 */
@AndroidIncompatible // depends on details of gc

import java.util.concurrent.CancellationException;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.TimeoutException;
import junit.framework.AssertionFailedError;
import org.checkerframework.checker.nullness.qual.Nullable;

/** Replacements for JUnit's {@code assertThrows} that work under GWT/J2CL. */
@GwtCompatible(emulated = true)
@ElementTypesAreNonnullByDefault
final class ReflectionFreeAssertThrows {

import java.util.Comparator;
import java.util.Iterator;
import java.util.NoSuchElementException;
import java.util.SortedSet;
import javax.annotation.CheckForNull;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * A sorted set which forwards all its method calls to another sorted set. Subclasses should
 * override one or more methods to modify the behavior of the backing sorted set as desired per the

    }

    @Override
    public E intern(E sample) {
      while (true) {
        // trying to read the canonical...
        @SuppressWarnings("rawtypes") // using raw types to avoid a bug in our nullness checker :(
        InternalEntry entry = map.getEntry(sample);
        if (entry != null) {
          Object canonical = entry.getKey();
          if (canonical != null) { // only matters if weak/soft keys are used

import java.util.concurrent.Executors;
import java.util.concurrent.Future;
import java.util.concurrent.ThreadFactory;
import java.util.concurrent.atomic.AtomicBoolean;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * Utilities necessary for working with libraries that supply plain {@link Future} instances. Note
 * that, whenever possible, it is strongly preferred to modify those libraries to return {@code

import com.google.common.annotations.GwtCompatible;
import com.google.errorprone.annotations.ForOverride;
import java.io.Serializable;
import javax.annotation.CheckForNull;
import org.checkerframework.checker.nullness.qual.NonNull;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * A strategy for determining whether two instances are considered equivalent, and for computing

import java.util.Collection;
import java.util.Iterator;
import java.util.List;
import java.util.ListIterator;
import javax.annotation.CheckForNull;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * A list which forwards all its method calls to another list. Subclasses should override one or
 * more methods to modify the behavior of the backing list as desired per the <a

import com.google.common.annotations.GwtCompatible;
import java.util.Comparator;
import java.util.Iterator;
import java.util.NavigableSet;
import javax.annotation.CheckForNull;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * A sorted multiset which forwards all its method calls to another sorted multiset. Subclasses
 * should override one or more methods to modify the behavior of the backing multiset as desired per

import java.util.logging.Level;
import java.util.logging.Logger;
import java.util.regex.MatchResult;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * Supplies an arbitrary "default" instance for a wide range of types, often useful in testing
 * utilities.
 *

import java.util.Collection;
import java.util.Collections;
import java.util.Comparator;
import java.util.Iterator;
import java.util.List;
import javax.annotation.CheckForNull;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * Provides static methods for working with {@code Collection} instances.
 *
 * <p><b>Java 8+ users:</b> several common uses for this class are now more comprehensively