Method keySet

android/guava/src/com/google/common/collect/Multimap.java:299–299

Returns a view collection of all <i>distinct</i> keys contained in this multimap. Note that the key set contains a key if and only if this multimap maps that key to at least one value. <p>Changes to the returned set will update the underlying multimap, and vice versa. However, <i>adding</i> to the

()

   * <i>adding</i> to the returned set is not possible.
   */
  Set<K> keySet();

  /**
   * Returns a view collection containing the key from each key-value pair in this multimap,