.addValue(Arrays.asList("C"))
            .addValue(Arrays.asList())
            .add(SHORT_NAME, Collections.singletonMap("k1", "v1"))
            .add(LONG_NAME, Collections.singletonMap("k2", "v2"))
            .addValue(Collections.singletonMap("k3", "v3"))
            .addValue(Collections.emptyMap())
            .addValue(null)
            .add(SHORT_NAME, java.util.Optional.of("1"))

public class StandardCrawlerContainer implements CrawlerContainer {

    private final Logger logger = LoggerFactory.getLogger(StandardCrawlerContainer.class);

    private final Map<String, ComponentHolder<?>> singletonMap = new ConcurrentHashMap<>();

    private final Map<String, ComponentDef<?>> prototypeMap = new ConcurrentHashMap<>();

    private boolean available = true;

    public StandardCrawlerContainer() {

import static com.google.common.collect.testing.features.MapFeature.SUPPORTS_REMOVE;
import static java.util.Collections.singletonList;
import static java.util.Collections.singletonMap;

import com.google.common.annotations.GwtCompatible;
import com.google.common.collect.Lists;
import com.google.common.collect.Maps;
import com.google.common.collect.testing.features.CollectionSize;

 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.google.common.collect;

import static java.util.Collections.singletonMap;

import com.google.common.annotations.GwtCompatible;
import java.util.Map.Entry;
import junit.framework.TestCase;
import org.checkerframework.checker.nullness.qual.Nullable;

/**

            .addValue(Arrays.asList("C"))
            .addValue(Arrays.asList())
            .add(SHORT_NAME, Collections.singletonMap("k1", "v1"))
            .add(LONG_NAME, Collections.singletonMap("k2", "v2"))
            .addValue(Collections.singletonMap("k3", "v3"))
            .addValue(Collections.emptyMap())
            .addValue(null)
            .add(SHORT_NAME, Optional.of("1"))

import static com.google.common.collect.testing.features.MapFeature.SUPPORTS_REMOVE;
import static java.util.Collections.singleton;
import static java.util.Collections.singletonMap;

import com.google.common.annotations.GwtCompatible;
import com.google.common.collect.Maps;
import com.google.common.collect.SetMultimap;
import com.google.common.collect.testing.features.CollectionSize;

import static com.google.common.collect.testing.features.MapFeature.SUPPORTS_REMOVE;
import static java.util.Collections.singleton;
import static java.util.Collections.singletonMap;

import com.google.common.annotations.GwtCompatible;
import com.google.common.collect.Maps;
import com.google.common.collect.SetMultimap;
import com.google.common.collect.testing.features.CollectionSize;

    public InputLocation(InputSource source) {
        this.lineNumber = -1;
        this.columnNumber = -1;
        this.source = source;
        this.locations = Collections.singletonMap(0, this);
        this.importedFrom = null;
    }

    public InputLocation(int lineNumber, int columnNumber) {
        this(lineNumber, columnNumber, null, null);
    }

              @Override
              protected Map<String, String> create(Entry<String, String>[] entries) {
                return singletonMap(entries[0].getKey(), entries[0].getValue());
              }
            })
        .named("singletonMap")
        .withFeatures(
            MapFeature.ALLOWS_NULL_KEYS,
            MapFeature.ALLOWS_NULL_VALUES,
            MapFeature.ALLOWS_ANY_NULL_QUERIES,

        NullPointerException.class,
        () -> builder.putAll(Collections.<String, Integer>singletonMap(null, 1)));
  }

  public void testBuilderPutNullValueViaPutAll() {
    Builder<String, Integer> builder = new Builder<>();
    assertThrows(
        NullPointerException.class,
        () -> builder.putAll(Collections.<String, Integer>singletonMap("one", null)));
  }

  @SuppressWarnings("AlwaysThrows")