public void testNullPointers() {
    NullPointerTester tester = new NullPointerTester();
    tester.testAllPublicStaticMethods(ImmutableSortedMap.class);
    tester.testAllPublicInstanceMethods(ImmutableSortedMap.<String, Integer>naturalOrder());
    tester.testAllPublicInstanceMethods(ImmutableSortedMap.of());
    tester.testAllPublicInstanceMethods(ImmutableSortedMap.of("one", 1));

  }

  public void testNullEqualityGroup() {
    EqualsTester tester = new EqualsTester();
    try {
      tester.addEqualityGroup((Object[]) null);
      fail();
    } catch (NullPointerException e) {
    }
  }

  public void testNullObjectInEqualityGroup() {
    EqualsTester tester = new EqualsTester();
    try {
      tester.addEqualityGroup(1, null, 3);
      fail();

  private final ForwardingWrapperTester tester = new ForwardingWrapperTester();

  public void testGoodForwarder() {
    tester.testForwarding(
        Arithmetic.class,
        new Function<Arithmetic, Arithmetic>() {
          @Override
          public Arithmetic apply(Arithmetic arithmetic) {
            return new ForwardingArithmetic(arithmetic);
          }
        });
    tester.testForwarding(

import java.util.Spliterator.OfPrimitive;
import java.util.function.Consumer;
import java.util.function.Function;
import java.util.function.Supplier;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * Tester for {@code Spliterator} implementations.
 *
 * @since 21.0
 */
@GwtCompatible
@ElementTypesAreNonnullByDefault
public final class SpliteratorTester<E extends @Nullable Object> {

  public void testNullPointers() {
    NullPointerTester tester = new NullPointerTester();
    tester.testAllPublicStaticMethods(Joiner.class);
    tester.testInstanceMethods(Joiner.on(","), NullPointerTester.Visibility.PACKAGE);
    tester.testInstanceMethods(Joiner.on(",").skipNulls(), NullPointerTester.Visibility.PACKAGE);
    tester.testInstanceMethods(

    NullPointerTester tester = new NullPointerTester();
    tester.testAllPublicInstanceMethods(InterfaceDefaultMethodChecksNull.create());
    try {
      tester.testAllPublicInstanceMethods(InterfaceDefaultMethodFailsToCheckNull.create());
    } catch (AssertionError expected) {
      return;
    }
    fail();
  }

  public void testDontAcceptIae() {
    NullPointerTester tester = new NullPointerTester();

    return stringWriter.toString();
  }

  /**
   * Returns the stack trace of {@code throwable}, possibly providing slower iteration over the full
   * trace but faster iteration over parts of the trace. Here, "slower" and "faster" are defined in
   * comparison to the normal way to access the stack trace, {@link Throwable#getStackTrace()

    return stringWriter.toString();
  }

  /**
   * Returns the stack trace of {@code throwable}, possibly providing slower iteration over the full
   * trace but faster iteration over parts of the trace. Here, "slower" and "faster" are defined in
   * comparison to the normal way to access the stack trace, {@link Throwable#getStackTrace()

  public void testNulls() throws Exception {
    NullPointerTester tester = new NullPointerTester();
    tester.testAllPublicStaticMethods(ImmutableListMultimap.class);
    tester.ignore(ImmutableListMultimap.class.getMethod("get", Object.class));
    tester.testAllPublicInstanceMethods(ImmutableListMultimap.of());
    tester.testAllPublicInstanceMethods(ImmutableListMultimap.of("a", 1));
  }

  public void testNulls() throws Exception {
    NullPointerTester tester = new NullPointerTester();
    tester.testAllPublicStaticMethods(ImmutableSetMultimap.class);
    tester.ignore(ImmutableSetMultimap.class.getMethod("get", Object.class));
    tester.testAllPublicInstanceMethods(ImmutableSetMultimap.of());
    tester.testAllPublicInstanceMethods(ImmutableSetMultimap.of("a", 1));
  }