return Collections.unmodifiableMap(super.column(columnKey));
    }

    @Override
    public Set<C> columnKeySet() {
      return Collections.unmodifiableSet(super.columnKeySet());
    }

    @Override
    public Map<C, Map<R, V>> columnMap() {
      return unmodifiableMap(Maps.transformValues(super.columnMap(), Collections::unmodifiableMap));
    }

    @Override

      return Collections.unmodifiableMap(super.column(columnKey));
    }

    @Override
    public Set<C> columnKeySet() {
      return Collections.unmodifiableSet(super.columnKeySet());
    }

    @Override
    public Map<C, Map<R, V>> columnMap() {
      return unmodifiableMap(Maps.transformValues(super.columnMap(), Collections::unmodifiableMap));
    }

    @Override

            new TestStringMapGenerator() {
              @Override
              protected Map<String, String> create(Entry<String, String>[] entries) {
                return unmodifiableMap(toHashMap(entries));
              }
            })
        .named("unmodifiableMap/HashMap")
        .withFeatures(
            MapFeature.ALLOWS_NULL_KEYS,
            MapFeature.ALLOWS_NULL_VALUES,
            MapFeature.ALLOWS_ANY_NULL_QUERIES,

            new TestStringMapGenerator() {
              @Override
              protected Map<String, String> create(Entry<String, String>[] entries) {
                return unmodifiableMap(toHashMap(entries));
              }
            })
        .named("unmodifiableMap/HashMap")
        .withFeatures(
            MapFeature.ALLOWS_NULL_KEYS,
            MapFeature.ALLOWS_NULL_VALUES,
            MapFeature.ALLOWS_ANY_NULL_QUERIES,

import static java.lang.Double.NEGATIVE_INFINITY;
import static java.lang.Double.NaN;
import static java.lang.Double.POSITIVE_INFINITY;
import static java.util.Arrays.sort;
import static java.util.Collections.unmodifiableMap;

import com.google.common.annotations.GwtIncompatible;
import com.google.common.annotations.J2ktIncompatible;
import com.google.common.primitives.Doubles;
import com.google.common.primitives.Ints;

            final Map.Entry entry = (Map.Entry) entries.next();
            entry.setValue(Collections.unmodifiableList((List) entry.getValue()));
        }
        return headerFields = Collections.unmodifiableMap(map);
    }

    @Override
    public Map getHeaderFields() {
        if (headerFields != null) {
            return headerFields;
        }
        try {
            handshake();

        return errorCode.getCategory();
    }

    public RetryPolicy getRetryPolicy() {
        return retryPolicy;
    }

    public Map<String, Object> getContext() {
        return Collections.unmodifiableMap(context);
    }

    public long getOperationStartTime() {
        return operationStartTime;
    }

    public String getOperationName() {
        return operationName;
    }

/** Returns an immutable wrap of this. */
@Suppress("NOTHING_TO_INLINE")
internal inline fun <K, V> Map<K, V>.unmodifiable(): Map<K, V> = Collections.unmodifiableMap(this)

/** Returns an immutable copy of this. */
@Suppress("UNCHECKED_CAST")
internal fun <T> List<T>.toImmutableList(): List<T> =
  when {
    this.isEmpty() -> emptyList()

        }
        for (final Entry<String, List<String>> entry : map.entrySet()) {
            entry.setValue(Collections.unmodifiableList(entry.getValue()));
        }
        return this.headerFields = Collections.unmodifiableMap(map);
    }

    @Override
    public Map<String, List<String>> getHeaderFields() {
        if (this.headerFields != null) {
            return this.headerFields;
        }
        handshake();

            properties.setProperty(key, value);
        }
    }

    @Override
    @Nonnull
    public Map<String, String> getProperties(@Nonnull Project project) {
        return Collections.unmodifiableMap(
                new PropertiesAsMap(getMavenProject(project).getProperties()));
    }

    @Override
    @Nonnull
    public Optional<Project> getExecutionProject(@Nonnull Project project) {