Class ImmutableMultimap<K,V>

All Implemented Interfaces:
Multimap<K,V>, Serializable
Direct Known Subclasses:
ImmutableListMultimap, ImmutableSetMultimap

public abstract class ImmutableMultimap<K,V> extends BaseImmutableMultimap<K,V> implements Serializable
A Multimap whose contents will never change, with many other important properties detailed at ImmutableCollection.

Warning: avoid direct usage of ImmutableMultimap as a type (as with Multimap itself). Prefer subtypes such as ImmutableSetMultimap or ImmutableListMultimap, which have well-defined AbstractMultimap.equals(java.lang.Object) semantics, thus avoiding a common source of bugs and confusion.

Note: every ImmutableMultimap offers an inverse() view, so there is no need for a distinct ImmutableBiMultimap type.

Key-grouped iteration. All view collections follow the same iteration order. In all current implementations, the iteration order always keeps multiple entries with the same key together. Any creation method that would customarily respect insertion order (such as copyOf(Multimap)) instead preserves key-grouped order by inserting entries for an existing key immediately after the last entry having that key.

See the Guava User Guide article on immutable collections.

Since:
2.0
See Also:
  • Field Details

  • Constructor Details

  • Method Details

    • of

      public static <K, V> ImmutableMultimap<K,V> of()
      Returns an empty multimap.

      Performance note: the instance returned is a singleton.

    • of

      public static <K, V> ImmutableMultimap<K,V> of(K k1, V v1)
      Returns an immutable multimap containing a single entry.
    • of

      public static <K, V> ImmutableMultimap<K,V> of(K k1, V v1, K k2, V v2)
      Returns an immutable multimap containing the given entries, in order.
    • of

      public static <K, V> ImmutableMultimap<K,V> of(K k1, V v1, K k2, V v2, K k3, V v3)
      Returns an immutable multimap containing the given entries, in the "key-grouped" insertion order described in the class documentation.
    • of

      public static <K, V> ImmutableMultimap<K,V> of(K k1, V v1, K k2, V v2, K k3, V v3, K k4, V v4)
      Returns an immutable multimap containing the given entries, in the "key-grouped" insertion order described in the class documentation.
    • of

      public static <K, V> ImmutableMultimap<K,V> of(K k1, V v1, K k2, V v2, K k3, V v3, K k4, V v4, K k5, V v5)
      Returns an immutable multimap containing the given entries, in the "key-grouped" insertion order described in the class documentation.
    • builder

      public static <K, V> ImmutableMultimap.Builder<K,V> builder()
      Returns a new builder. The generated builder is equivalent to the builder created by the ImmutableMultimap.Builder constructor.
    • builderWithExpectedKeys

      public static <K, V> ImmutableMultimap.Builder<K,V> builderWithExpectedKeys(int expectedKeys)
      Returns a new builder with a hint for how many distinct keys are expected to be added. The generated builder is equivalent to that returned by builder(), but may perform better if expectedKeys is a good estimate.
      Throws:
      IllegalArgumentException - if expectedKeys is negative
      Since:
      33.3.0
    • copyOf

      public static <K, V> ImmutableMultimap<K,V> copyOf(Multimap<? extends K,? extends V> multimap)
      Returns an immutable multimap containing the same mappings as multimap, in the "key-grouped" iteration order described in the class documentation.

      Despite the method name, this method attempts to avoid actually copying the data when it is safe to do so. The exact circumstances under which a copy will or will not be performed are undocumented and subject to change.

      Throws:
      NullPointerException - if any key or value in multimap is null
    • copyOf

      public static <K, V> ImmutableMultimap<K,V> copyOf(Iterable<? extends Map.Entry<? extends K,? extends V>> entries)
      Returns an immutable multimap containing the specified entries. The returned multimap iterates over keys in the order they were first encountered in the input, and the values for each key are iterated in the order they were encountered.
      Throws:
      NullPointerException - if any key, value, or entry is null
      Since:
      19.0
    • removeAll

      @Deprecated public ImmutableCollection<V> removeAll(@CheckForNull Object key)
      Deprecated.
      Unsupported operation.
      Guaranteed to throw an exception and leave the multimap unmodified.
      Specified by:
      removeAll in interface Multimap<K,V>
      Returns:
      the values that were removed (possibly empty). The returned collection may be modifiable, but updating it will have no effect on the multimap.
      Throws:
      UnsupportedOperationException - always
    • replaceValues

      @Deprecated public ImmutableCollection<V> replaceValues(K key, Iterable<? extends V> values)
      Deprecated.
      Unsupported operation.
      Guaranteed to throw an exception and leave the multimap unmodified.
      Specified by:
      replaceValues in interface Multimap<K,V>
      Overrides:
      replaceValues in class AbstractMultimap<K,V>
      Returns:
      the collection of replaced values, or an empty collection if no values were previously associated with the key. The collection may be modifiable, but updating it will have no effect on the multimap.
      Throws:
      UnsupportedOperationException - always
    • clear

      @Deprecated public final void clear()
      Deprecated.
      Unsupported operation.
      Guaranteed to throw an exception and leave the multimap unmodified.
      Specified by:
      clear in interface Multimap<K,V>
      Throws:
      UnsupportedOperationException - always
    • get

      public abstract ImmutableCollection<V> get(K key)
      Returns an immutable collection of the values for the given key. If no mappings in the multimap have the provided key, an empty immutable collection is returned. The values are in the same order as the parameters used to build this multimap.
      Specified by:
      get in interface Multimap<K,V>
    • inverse

      public abstract ImmutableMultimap<V,K> inverse()
      Returns an immutable multimap which is the inverse of this one. For every key-value mapping in the original, the result will have a mapping with key and value reversed.
      Since:
      11.0
    • put

      @Deprecated public final boolean put(K key, V value)
      Deprecated.
      Unsupported operation.
      Guaranteed to throw an exception and leave the multimap unmodified.
      Specified by:
      put in interface Multimap<K,V>
      Overrides:
      put in class AbstractMultimap<K,V>
      Returns:
      true if the method increased the size of the multimap, or false if the multimap already contained the key-value pair and doesn't allow duplicates
      Throws:
      UnsupportedOperationException - always
    • putAll

      @Deprecated public final boolean putAll(K key, Iterable<? extends V> values)
      Deprecated.
      Unsupported operation.
      Guaranteed to throw an exception and leave the multimap unmodified.
      Specified by:
      putAll in interface Multimap<K,V>
      Overrides:
      putAll in class AbstractMultimap<K,V>
      Returns:
      true if the multimap changed
      Throws:
      UnsupportedOperationException - always
    • putAll

      @Deprecated public final boolean putAll(Multimap<? extends K,? extends V> multimap)
      Deprecated.
      Unsupported operation.
      Guaranteed to throw an exception and leave the multimap unmodified.
      Specified by:
      putAll in interface Multimap<K,V>
      Overrides:
      putAll in class AbstractMultimap<K,V>
      Returns:
      true if the multimap changed
      Throws:
      UnsupportedOperationException - always
    • remove

      @Deprecated public final boolean remove(@CheckForNull Object key, @CheckForNull Object value)
      Deprecated.
      Unsupported operation.
      Guaranteed to throw an exception and leave the multimap unmodified.
      Specified by:
      remove in interface Multimap<K,V>
      Overrides:
      remove in class AbstractMultimap<K,V>
      Returns:
      true if the multimap changed
      Throws:
      UnsupportedOperationException - always
    • isPartialView

      boolean isPartialView()
      Returns true if this immutable multimap's implementation contains references to user-created objects that aren't accessible via this multimap's methods. This is generally used to determine whether copyOf implementations should make an explicit copy to avoid memory leaks.
    • containsKey

      public boolean containsKey(@CheckForNull Object key)
      Description copied from interface: Multimap
      Returns true if this multimap contains at least one key-value pair with the key key.
      Specified by:
      containsKey in interface Multimap<K,V>
    • containsValue

      public boolean containsValue(@CheckForNull Object value)
      Description copied from interface: Multimap
      Returns true if this multimap contains at least one key-value pair with the value value.
      Specified by:
      containsValue in interface Multimap<K,V>
      Overrides:
      containsValue in class AbstractMultimap<K,V>
    • size

      public int size()
      Description copied from interface: Multimap
      Returns the number of key-value pairs in this multimap.

      Note: this method does not return the number of distinct keys in the multimap, which is given by keySet().size() or asMap().size(). See the opening section of the Multimap class documentation for clarification.

      Specified by:
      size in interface Multimap<K,V>
    • keySet

      public ImmutableSet<K> keySet()
      Returns an immutable set of the distinct keys in this multimap, in the same order as they appear in this multimap.
      Specified by:
      keySet in interface Multimap<K,V>
      Overrides:
      keySet in class AbstractMultimap<K,V>
    • createKeySet

      Set<K> createKeySet()
      Specified by:
      createKeySet in class AbstractMultimap<K,V>
    • asMap

      public ImmutableMap<K,Collection<V>> asMap()
      Returns an immutable map that associates each key with its corresponding values in the multimap. Keys and values appear in the same order as in this multimap.
      Specified by:
      asMap in interface Multimap<K,V>
      Overrides:
      asMap in class AbstractMultimap<K,V>
    • createAsMap

      Map<K,Collection<V>> createAsMap()
      Specified by:
      createAsMap in class AbstractMultimap<K,V>
    • entries

      public ImmutableCollection<Map.Entry<K,V>> entries()
      Returns an immutable collection of all key-value pairs in the multimap.
      Specified by:
      entries in interface Multimap<K,V>
      Overrides:
      entries in class AbstractMultimap<K,V>
    • createEntries

      ImmutableCollection<Map.Entry<K,V>> createEntries()
      Specified by:
      createEntries in class AbstractMultimap<K,V>
    • entryIterator

      UnmodifiableIterator<Map.Entry<K,V>> entryIterator()
      Specified by:
      entryIterator in class AbstractMultimap<K,V>
    • entrySpliterator

      Spliterator<Map.Entry<K,V>> entrySpliterator()
      Overrides:
      entrySpliterator in class AbstractMultimap<K,V>
    • forEach

      public void forEach(BiConsumer<? super K,? super V> action)
      Description copied from interface: Multimap
      Performs the given action for all key-value pairs contained in this multimap. If an ordering is specified by the Multimap implementation, actions will be performed in the order of iteration of Multimap.entries(). Exceptions thrown by the action are relayed to the caller.

      To loop over all keys and their associated value collections, write Multimaps.asMap(multimap).forEach((key, valueCollection) -> action()).

      Specified by:
      forEach in interface Multimap<K,V>
    • keys

      public ImmutableMultiset<K> keys()
      Returns an immutable multiset containing all the keys in this multimap, in the same order and with the same frequencies as they appear in this multimap; to get only a single occurrence of each key, use keySet().
      Specified by:
      keys in interface Multimap<K,V>
      Overrides:
      keys in class AbstractMultimap<K,V>
    • createKeys

      ImmutableMultiset<K> createKeys()
      Specified by:
      createKeys in class AbstractMultimap<K,V>
    • values

      public ImmutableCollection<V> values()
      Returns an immutable collection of the values in this multimap. Its iterator traverses the values for the first key, the values for the second key, and so on.
      Specified by:
      values in interface Multimap<K,V>
      Overrides:
      values in class AbstractMultimap<K,V>
    • createValues

      ImmutableCollection<V> createValues()
      Specified by:
      createValues in class AbstractMultimap<K,V>
    • valueIterator

      UnmodifiableIterator<V> valueIterator()
      Overrides:
      valueIterator in class AbstractMultimap<K,V>