import org.apache.maven.api.annotations.Experimental;

/**
 * Base class for all maven exceptions carrying {@link BuilderProblem}s.
 *
 * @since 4.0.0
 */
@Experimental
public abstract class MavenBuilderException extends MavenException {

    /**
     * The collection of problems associated with this exception.
     */
    private final ProblemCollector<BuilderProblem> problems;

    /**

import java.io.IOException;

/**
 * Signals a failure to parse the metadata due to invalid syntax (e.g. non well formed XML or unknown elements).
 *
 */
public class MetadataParseException extends IOException {

    /**
     * The one-based index of the line containing the error.
     */
    private final int lineNumber;

    /**
     * The one-based index of the column containing the error.
     */

// @Ignore affects the Android test runner, which respects JUnit 4 annotations on JUnit 3 tests.
@SuppressWarnings("JUnit4ClassUsedInJUnit3")
@NullMarked
public class MultimapPutTester<K extends @Nullable Object, V extends @Nullable Object>
    extends AbstractMultimapTester<K, V, Multimap<K, V>> {
  @MapFeature.Require(absent = SUPPORTS_PUT)
  public void testPutUnsupported() {

import org.jspecify.annotations.Nullable;

/**
 * Tests for {@code ForwardingNavigableSet}.
 *
 * @author Louis Wasserman
 */
@NullUnmarked
public class ForwardingNavigableSetTest extends TestCase {
  static class StandardImplForwardingNavigableSet<T> extends ForwardingNavigableSet<T> {
    private final NavigableSet<T> backingSet;

    StandardImplForwardingNavigableSet(NavigableSet<T> backingSet) {
      this.backingSet = backingSet;
    }

 * @author Jon Noack
 */
@GwtIncompatible // not worth using in GWT for now
class CompactHashSet<E extends @Nullable Object> extends AbstractSet<E> implements Serializable {
  // TODO(user): cache all field accesses in local vars

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

  /**

-->

#### Special notes for your reviewer:

#### Does this PR introduce a user-facing change?
<!--
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 * {@code entrySet()} implementation for {@link ImmutableMap}.
 *
 * @author Jesse Wilson
 * @author Kevin Bourrillion
 */
@GwtCompatible
abstract class ImmutableMapEntrySet<K, V> extends ImmutableSet<Entry<K, V>> {
  static final class RegularEntrySet<K, V> extends ImmutableMapEntrySet<K, V> {
    private final transient ImmutableMap<K, V> map;
    private final transient ImmutableList<Entry<K, V>> entries;

    checkNotNull(interfaceType);
    checkNotNull(timeoutUnit);
    return target; // ha ha
  }

  @CanIgnoreReturnValue // TODO(kak): consider removing this
  @Override
  @ParametricNullness
  public <T extends @Nullable Object> T callWithTimeout(
      Callable<T> callable, long timeoutDuration, TimeUnit timeoutUnit) throws ExecutionException {
    checkNotNull(callable);
    checkNotNull(timeoutUnit);
    try {

 * {@link #set}, or {@link #add}.
 *
 * @author Jared Levy
 */
@GwtCompatible
abstract class AbstractIndexedListIterator<E extends @Nullable Object>
    extends UnmodifiableListIterator<E> {
  private final int size;
  private int position;

  /** Returns the element with the specified index. This method is called by {@link #next()}. */
  @ParametricNullness

import java.io.Reader;
import java.io.StringReader;
import junit.framework.TestCase;
import org.jspecify.annotations.NullUnmarked;

/**
 * @author ricebin
 */
@NullUnmarked
public class MultiReaderTest extends TestCase {

  public void testOnlyOneOpen() throws Exception {
    String testString = "abcdefgh";
    CharSource source = newCharSource(testString);
    int[] counter = new int[1];
    CharSource reader =