private Iterables() {}

  /** Returns an unmodifiable view of {@code iterable}. */
  public static <T extends @Nullable Object> Iterable<T> unmodifiableIterable(
      Iterable<? extends T> iterable) {
    checkNotNull(iterable);
    if (iterable instanceof UnmodifiableIterable || iterable instanceof ImmutableCollection) {
      @SuppressWarnings("unchecked") // Since it's unmodifiable, the covariant cast is safe

  }

  /**
   * Returns an unmodifiable view of the specified set of entries. The {@link Entry#setValue}
   * operation throws an {@link UnsupportedOperationException}, as do any operations that would
   * modify the returned set.
   *
   * @param entrySet the entries for which to return an unmodifiable view
   * @return an unmodifiable view of the entries
   */

  }

  // TODO(jlevy): Add eraseRow and eraseColumn methods?

  @Override
  public int size() {
    return rowList.size() * columnList.size();
  }

  /**
   * Returns an unmodifiable set of all row key / column key / value triplets. Changes to the table
   * will update the returned set.
   *
   * <p>The returned set's iterator traverses the mappings with the first row key, the mappings with

    this.map = map;
    totalSize = 0;
    for (Collection<V> values : map.values()) {
      checkArgument(!values.isEmpty());
      totalSize += values.size();
    }
  }

  /**
   * Creates an unmodifiable, empty collection of values.
   *
   * <p>This is used in {@link #removeAll} on an empty key.
   */
  Collection<V> createUnmodifiableEmptyCollection() {
    return unmodifiableCollectionSubclass(createCollection());

    /* No aliasing on inverse operations. */
    assertSame(unmod.inverse(), unmod.inverse());
    assertSame(unmod, unmod.inverse().inverse());

    /* Unmodifiable is a view. */
    mod.put(4, "four");
    assertEquals(true, unmod.get(4).equals("four"));
    assertEquals(true, unmod.inverse().get("four").equals(4));

    /* No aliasing on inverse operations. */
    assertSame(unmod.inverse(), unmod.inverse());
    assertSame(unmod, unmod.inverse().inverse());

    /* Unmodifiable is a view. */
    mod.put(4, "four");
    assertEquals(true, unmod.get(4).equals("four"));
    assertEquals(true, unmod.inverse().get("four").equals(4));

 * value and the old value.
 *
 * <p>Keys and values may be null. All optional multimap methods are supported, and all returned
 * views are modifiable.
 *
 * <p>The lists returned by {@link #get}, {@link #removeAll}, and {@link #replaceValues} all
 * implement {@link java.util.RandomAccess}.
 *

        assertEquals(123, metaDataMap.get("key2"));
        assertEquals(true, metaDataMap.get("key3"));
    }

    public void test_metaDataMapModifiable() {
        // Test that metadata map is modifiable
        ResponseData data = new ResponseData();

        data.addMetaData("key1", "value1");

        Map<String, Object> metaDataMap = data.getMetaDataMap();
        metaDataMap.put("key2", "value2");