/**
   * Determines whether two possibly-null objects are equal. Returns:
   *
   * <ul>
   *   <li>{@code true} if {@code a} and {@code b} are both null.
   *   <li>{@code true} if {@code a} and {@code b} are both non-null and they are equal according to
   *       {@link Object#equals(Object)}.
   *   <li>{@code false} in all other situations.
   * </ul>
   *

 *       typically because the type forbids nullable type arguments: For example, {@code
 *       ImmutableList.get} returns {@code E}, but that value is never {@code null}. (Accordingly,
 *       {@code ImmutableList} is declared to forbid {@code ImmutableList<@Nullable String>}.)
 *   <li>methods whose return type is a type variable but which can return {@code null} regardless

 *       typically because the type forbids nullable type arguments: For example, {@code
 *       ImmutableList.get} returns {@code E}, but that value is never {@code null}. (Accordingly,
 *       {@code ImmutableList} is declared to forbid {@code ImmutableList<@Nullable String>}.)
 *   <li>methods whose return type is a type variable but which can return {@code null} regardless

        return builder()
                .session(requireNonNull(session, "session cannot be null"))
                .artifactCoordinates(requireNonNull(artifactCoordinates, "artifactCoordinates cannot be null"))
                .build();
    }

    @Nonnull
    static VersionResolverRequest build(
            @Nonnull Session session,

    // Check cache. We use == on purpose because it's cheaper and a cache miss is ok.
    if (entry != null && entry.getKey() == key) {
      return entry.getValue();
    }
    return null;
  }

  void clearCache() {
    cacheEntry = null;
  }

./mc mb -l myminio/versioned

./mc mirror internal myminio/versioned/ --quiet >/dev/null

## Soft delete (creates delete markers)
./mc rm -r --force myminio/versioned >/dev/null

## mirror again to create another set of version on top
./mc mirror internal myminio/versioned/ --quiet >/dev/null

expected_checksum=$(./mc cat internal/dsync/drwmutex.go | md5sum)

    fakeTicker.advance(2, MILLISECONDS);
    assertEquals(null, cache.getIfPresent(10));
    assertEquals(null, cache.getIfPresent(20));
    assertEquals(null, cache.getIfPresent(4));

    cache.put(10, 20);
    assertEquals(Integer.valueOf(20), cache.getIfPresent(10));

    fakeTicker.advance(1000, MILLISECONDS);
    assertEquals(null, cache.getIfPresent(10));
  }

  public void testSetCount_addNull_nullSupported() {
    assertSetCount(null, 1);
  }

  @CollectionFeature.Require(value = SUPPORTS_ADD, absent = ALLOWS_NULL_VALUES)
  public void testSetCount_addNull_nullUnsupported() {
    assertThrows(NullPointerException.class, () -> setCountNoCheckReturnValue(null, 1));
  }

  @CollectionFeature.Require(ALLOWS_NULL_VALUES)

         * @return The absolute file path of the resource, or null if not found
         */
        protected String getResourcePath(final String path) {
            final File file = ResourceUtil.getResourceAsFileNoException(path);
            if (file != null) {
                return file.getAbsolutePath();
            }
            return null;
        }

        /**

      @Nullable Type ownerType, Class<?> rawType, Type... arguments) {
    if (ownerType == null) {
      return newParameterizedType(rawType, arguments);
    }
    // ParameterizedTypeImpl constructor already checks, but we want to throw NPE before IAE
    checkNotNull(arguments);
    checkArgument(rawType.getEnclosingClass() != null, "Owner type for unenclosed %s", rawType);
    return new ParameterizedTypeImpl(ownerType, rawType, arguments);