Class ImmutableMultimap<K,V>

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


    @GwtCompatible(emulated=true)
    public abstract class ImmutableMultimap<K,V>
    extends Object
    implements Serializable
    An immutable Multimap. Does not permit null keys or values.

    Unlike Multimaps.unmodifiableMultimap(Multimap), which is a view of a separate multimap which can still change, an instance of ImmutableMultimap contains its own data and will never change. ImmutableMultimap is convenient for public static final multimaps ("constant multimaps") and also lets you easily make a "defensive copy" of a multimap provided to your class by a caller.

    Note: Although this class is not final, it cannot be subclassed as it has no public or protected constructors. Thus, instances of this class are guaranteed to be immutable.

    In addition to methods defined by Multimap, an inverse() method is also supported.

    See the Guava User Guide article on immutable collections.

    Since:
    2.0 (imported from Google Collections Library)
    See Also:
    Serialized Form
    • Nested Class Summary

      Nested Classes

      Modifier and Type Class and Description
      static class  ImmutableMultimap.Builder<K,V>
      A builder for creating immutable multimap instances, especially public static final multimaps ("constant multimaps").
    • Method Summary

      Modifier and Type Method and Description
      ImmutableMap<K,Collection<V>> asMap()
      Returns an immutable map that associates each key with its corresponding values in the multimap.
      static <K,V> ImmutableMultimap.Builder<K,V> builder()
      Returns a new builder.
      void clear()
      Deprecated. 
      Unsupported operation.
      boolean containsEntry(Object key, Object value)
      Returns true if this multimap contains at least one key-value pair with the key key and the value value.
      boolean containsKey(Object key)
      Returns true if this multimap contains at least one key-value pair with the key key.
      boolean containsValue(Object value)
      Returns true if this multimap contains at least one key-value pair with the value value.
      static <K,V> ImmutableMultimap<K,V> copyOf(Multimap<? extends K,? extends V> multimap)
      Returns an immutable multimap containing the same mappings as multimap.
      ImmutableCollection<Map.Entry<K,V>> entries()
      Returns an immutable collection of all key-value pairs in the multimap.
      boolean equals(Object object)
      Compares the specified object with this multimap for equality.
      abstract ImmutableCollection<V> get(K key)
      Returns an immutable collection of the values for the given key.
      int hashCode()
      Returns the hash code for this multimap.
      abstract ImmutableMultimap<V,K> inverse()
      Returns an immutable multimap which is the inverse of this one.
      boolean isEmpty()
      Returns true if this multimap contains no key-value pairs.
      ImmutableMultiset<K> keys()
      Returns a collection, which may contain duplicates, of all keys.
      ImmutableSet<K> keySet()
      Returns an immutable set of the distinct keys in this multimap.
      static <K,V> ImmutableMultimap<K,V> of()
      Returns an empty multimap.
      static <K,V> ImmutableMultimap<K,V> of(K k1, V v1)
      Returns an immutable multimap containing a single entry.
      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.
      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 order.
      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 order.
      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 order.
      boolean put(K key, V value)
      Deprecated. 
      Unsupported operation.
      boolean putAll(K key, Iterable<? extends V> values)
      Deprecated. 
      Unsupported operation.
      boolean putAll(Multimap<? extends K,? extends V> multimap)
      Deprecated. 
      Unsupported operation.
      boolean remove(Object key, Object value)
      Deprecated. 
      Unsupported operation.
      ImmutableCollection<V> removeAll(Object key)
      Deprecated. 
      Unsupported operation.
      ImmutableCollection<V> replaceValues(K key, Iterable<? extends V> values)
      Deprecated. 
      Unsupported operation.
      int size()
      Returns the number of key-value pairs in this multimap.
      String toString()
      Returns a string representation of the multimap, generated by calling toString on the map returned by Multimap.asMap().
      ImmutableCollection<V> values()
      Returns an immutable collection of the values in this multimap.
    • Method Detail

      • 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 order.
      • 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 order.
      • 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 order.
      • 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. The generated multimap's key and value orderings correspond to the iteration ordering of the multimap.asMap() view.

        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
      • removeAll

        @Deprecated
        public ImmutableCollection<V> removeAll(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>
        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
      • 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.
      • 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 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>
        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
      • containsKey

        public boolean containsKey(Object key)
        Description copied from interface: Multimap
        Returns true if this multimap contains at least one key-value pair with the key key.
      • containsValue

        public boolean containsValue(Object value)
        Description copied from interface: Multimap
        Returns true if this multimap contains at least one key-value pair with the value value.
      • 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.

      • keySet

        public ImmutableSet<K> keySet()
        Returns an immutable set of the distinct keys in this multimap. These keys are ordered according to when they first appeared during the construction of this multimap.
      • asMap

        public ImmutableMap<K,Collection<V>> asMap()
        Returns an immutable map that associates each key with its corresponding values in the multimap.
      • entries

        public ImmutableCollection<Map.Entry<K,V>> entries()
        Returns an immutable collection of all key-value pairs in the multimap. Its iterator traverses the values for the first key, the values for the second key, and so on.
      • keys

        public ImmutableMultiset<K> keys()
        Returns a collection, which may contain duplicates, of all keys. The number of times a key appears in the returned multiset equals the number of mappings the key has in the multimap. Duplicate keys appear consecutively in the multiset's iteration order.
      • 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.
      • isEmpty

        public boolean isEmpty()
        Description copied from interface: Multimap
        Returns true if this multimap contains no key-value pairs. Equivalent to size() == 0, but can in some cases be more efficient.
      • containsEntry

        public boolean containsEntry(Object key,
                                     Object value)
        Description copied from interface: Multimap
        Returns true if this multimap contains at least one key-value pair with the key key and the value value.
      • equals

        public boolean equals(Object object)
        Description copied from interface: Multimap
        Compares the specified object with this multimap for equality. Two multimaps are equal when their map views, as returned by Multimap.asMap(), are also equal.

        In general, two multimaps with identical key-value mappings may or may not be equal, depending on the implementation. For example, two SetMultimap instances with the same key-value mappings are equal, but equality of two ListMultimap instances depends on the ordering of the values for each key.

        A non-empty SetMultimap cannot be equal to a non-empty ListMultimap, since their Multimap.asMap() views contain unequal collections as values. However, any two empty multimaps are equal, because they both have empty Multimap.asMap() views.

      • toString

        public String toString()
        Returns a string representation of the multimap, generated by calling toString on the map returned by Multimap.asMap().
        Overrides:
        toString in class  Object
        Returns:
        a string representation of the multimap