contributions from many people at Google, as well as:

1ndig0, 372046933, abhinav, afzpatel, Akhil Goel, Alain Carlucci, Aleksei, Alen Huang, Alex, Amrinfathima-Mcw, Aravindh Balaji, Armand Picard, Aseem Athale, Ashiq Imran, Assoap, Chao, Chase Riley Roberts, Chenhao Jiang, chunhsue, chuntl, Chunyu Jin, Corentin Kerisit, Crefeda Rodrigues, dependabot[bot], Dragan Mladjenovic, Elen Kalda, Felix Thomasmathibalan, gabeweisz, Gauri Deshpande, Georg Stefan Schmid, Guozhong Zhuang, Harsha H S, Harshith_N, Hugo...

import java.util.ListIterator;
import junit.framework.TestCase;
import org.jspecify.annotations.NullUnmarked;

/**
 * Tests for {@code ForwardingListIterator}.
 *
 * @author Robert Konigsberg
 */
@NullUnmarked
public class ForwardingListIteratorTest extends TestCase {

  @SuppressWarnings("rawtypes")
  public void testForwarding() {
    new ForwardingWrapperTester()
        .testForwarding(

import java.util.ListIterator;
import junit.framework.TestCase;
import org.jspecify.annotations.NullUnmarked;

/**
 * Tests for {@code ForwardingListIterator}.
 *
 * @author Robert Konigsberg
 */
@NullUnmarked
public class ForwardingListIteratorTest extends TestCase {

  @SuppressWarnings("rawtypes")
  public void testForwarding() {
    new ForwardingWrapperTester()
        .testForwarding(

import junit.framework.Test;
import junit.framework.TestCase;
import junit.framework.TestSuite;
import org.jspecify.annotations.NullUnmarked;

/**
 * Tests for {@link ForwardingCollection}.
 *
 * @author Robert Konigsberg
 * @author Hayward Chan
 * @author Louis Wasserman
 */
@NullUnmarked
public class ForwardingCollectionTest extends TestCase {

import junit.framework.TestCase;
import junit.framework.TestSuite;
import org.jspecify.annotations.NullUnmarked;
import org.jspecify.annotations.Nullable;

/**
 * Tests for {@code ForwardingQueue}.
 *
 * @author Robert Konigsberg
 * @author Louis Wasserman
 */
@NullUnmarked
public class ForwardingQueueTest extends TestCase {

  static final class StandardImplForwardingQueue<T> extends ForwardingQueue<T> {

import junit.framework.TestCase;
import junit.framework.TestSuite;
import org.jspecify.annotations.NullUnmarked;
import org.jspecify.annotations.Nullable;

/**
 * Tests for {@code ForwardingSet}.
 *
 * @author Robert Konigsberg
 * @author Louis Wasserman
 */
@NullUnmarked
public class ForwardingSetTest extends TestCase {
  static class StandardImplForwardingSet<T> extends ForwardingSet<T> {
    private final Set<T> backingSet;

import junit.framework.TestCase;
import junit.framework.TestSuite;
import org.jspecify.annotations.NullUnmarked;
import org.jspecify.annotations.Nullable;

/**
 * Tests for {@code ForwardingList}.
 *
 * @author Robert Konigsberg
 * @author Louis Wasserman
 */
@NullUnmarked
public class ForwardingListTest extends TestCase {
  static final class StandardImplForwardingList<T> extends ForwardingList<T> {

import junit.framework.TestCase;
import junit.framework.TestSuite;
import org.jspecify.annotations.NullUnmarked;
import org.jspecify.annotations.Nullable;

/**
 * Tests for {@code ForwardingSet}.
 *
 * @author Robert Konigsberg
 * @author Louis Wasserman
 */
@NullUnmarked
public class ForwardingSetTest extends TestCase {
  static class StandardImplForwardingSet<T> extends ForwardingSet<T> {
    private final Set<T> backingSet;

import junit.framework.TestCase;
import junit.framework.TestSuite;
import org.jspecify.annotations.NullUnmarked;
import org.jspecify.annotations.Nullable;

/**
 * Tests for {@code ForwardingSortedMap}.
 *
 * @author Robert KonigsbergSortedMapFeature
 */
@NullUnmarked
public class ForwardingSortedMapTest extends TestCase {
  static class StandardImplForwardingSortedMap<K, V> extends ForwardingSortedMap<K, V> {

import junit.framework.TestCase;
import junit.framework.TestSuite;
import org.jspecify.annotations.NullUnmarked;
import org.jspecify.annotations.Nullable;

/**
 * Tests for {@code ForwardingNavigableMap}.
 *
 * @author Robert Konigsberg
 * @author Louis Wasserman
 */
@NullUnmarked
public class ForwardingNavigableMapTest extends TestCase {
  static class StandardImplForwardingNavigableMap<K, V> extends ForwardingNavigableMap<K, V> {