*
     * @throws IllegalArgumentException if duplicate keys were added
     */
    public ImmutableMap<K, V> build() {
      return buildOrThrow();
    }

    /**
     * Returns a newly-created immutable map, or throws an exception if any key was added more than
     * once. The iteration order of the returned map is the order in which entries were inserted

       * parameters. If it were statically checked, the checker would still be OK with it, since
       * we're copying into a `contents` array whose type allows it to contain nulls. Still, it's
       * worth noting that we promise not to put nulls into the array in the first `size` elements.
       * We uphold that promise here because our callers promise that `elements` will not contain

  @SuppressWarnings("unchecked")
  public static <T extends @Nullable Object> Collector<T, ?, T> onlyElement() {
    return (Collector) ONLY_ELEMENT;
  }

  /**
   * This atrocity is here to let us report several of the elements in the stream if there were more
   * than one, not just two.
   */
  @SuppressWarnings("EmptyList") // ImmutableList doesn't support nullable element types
  private static final class ToOptionalState {

        assertEquals("field1:value1", facetQueryView.getQueryMap().get("label1"));
        assertEquals("field2:value2", facetQueryView.getQueryMap().get("label2"));

        // Check that queries were added to FacetInfo
        assertEquals(2, testFacetInfo.getAddedQueries().size());
        assertTrue(testFacetInfo.getAddedQueries().contains("field1:value1"));

import java.util.Iterator;
import java.util.NoSuchElementException;

import org.codelibs.core.exception.ClUnsupportedOperationException;

/**
 * An {@link Iterator} that iterates over multiple {@link Iterator}s as if they were a single {@link Iterator}.
 * <p>
 * Usage example:
 * </p>
 *
 * <pre>
 * import static org.codelibs.core.collection.MultiIterator.*;
 *
 * List&lt;String&gt; list = ...;
 * Set&lt;String&gt; set = ...;

  static final String NODE_REMOVED_FROM_GRAPH =
      "Node %s that was used to generate this set is no longer in the graph.";
  static final String NODE_PAIR_REMOVED_FROM_GRAPH =
      "Node %s or node %s that were used to generate this set are no longer in the graph.";
  static final String EDGE_REMOVED_FROM_GRAPH =
      "Edge %s that was used to generate this set is no longer in the graph.";
  static final String REUSING_EDGE =

  @SuppressWarnings("unchecked")
  public static <T extends @Nullable Object> Collector<T, ?, T> onlyElement() {
    return (Collector) ONLY_ELEMENT;
  }

  /**
   * This atrocity is here to let us report several of the elements in the stream if there were more
   * than one, not just two.
   */
  @SuppressWarnings("EmptyList") // ImmutableList doesn't support nullable element types
  private static final class ToOptionalState {

    latch.countDown();

    exec.shutdown();
    exec.awaitTermination(100, MILLISECONDS);
  }

  /**
   * Tests that all listeners complete, even if they were added before or after the future was
   * finishing. Also acts as a concurrency test to make sure the locking is done correctly when a
   * future is finishing so that no listeners can be lost.
   */

  final Collection<? extends Throwable> exceptions;

  private ClusterException(Collection<? extends Throwable> exceptions) {
    super(
        exceptions.size() + " exceptions were thrown. The first exception is listed as a cause.",
        exceptions.iterator().next());
    ArrayList<? extends Throwable> temp = new ArrayList<>(exceptions);
    this.exceptions = Collections.unmodifiableCollection(temp);
  }

  }

  /** Returns the number of times {@link Cache} lookup methods have returned a cached value. */
  public long hitCount() {
    return hitCount;
  }

  /**
   * Returns the ratio of cache requests which were hits. This is defined as {@code hitCount /
   * requestCount}, or {@code 1.0} when {@code requestCount == 0}. Note that {@code hitRate +
   * missRate =~ 1.0}.
   */
  public double hitRate() {