Class EmptyMap<K,​V>

    • Constructor Detail

      • EmptyMap

        EmptyMap()
    • Method Detail

      • readResolve

        private java.lang.Object readResolve()
      • size

        public int size()
        Description copied from interface: RichIterable
        Returns the number of items in this iterable.
        Specified by:
        size in interface java.util.Map<K,​V>
        Specified by:
        size in interface RichIterable<K>
      • withKeyValue

        public MutableMap<K,​V> withKeyValue​(K addKey,
                                                  V addValue)
        Description copied from interface: MutableMapIterable
        This method allows mutable, fixed size, and immutable maps the ability to add elements to their existing elements. In order to support fixed size maps, a new instance of a map would have to be returned including the keys and values of the original plus the additional key and value. In the case of mutable maps, the original map is modified and then returned. In order to use this method properly with mutable and fixed size maps the following approach must be taken:
         map = map.withKeyValue("new key", "new value");
         
        In the case of FixedSizeMap, a new instance will be returned by withKeyValue, and any variables that previously referenced the original map will need to be redirected to reference the new instance. In the case of a FastMap or UnifiedMap, you will be replacing the reference to map with map, since FastMap and UnifiedMap will both return "this" after calling put on themselves.
        Specified by:
        withKeyValue in interface MutableMap<K,​V>
        Specified by:
        withKeyValue in interface MutableMapIterable<K,​V>
        Overrides:
        withKeyValue in class AbstractMutableMap<K,​V>
        See Also:
        Map.put(Object, Object)
      • withoutKey

        public MutableMap<K,​V> withoutKey​(K key)
        Description copied from interface: MutableMapIterable
        This method allows mutable, fixed size, and immutable maps the ability to remove elements from their existing elements. In order to support fixed size maps, a new instance of a map would have to be returned including the keys and values of the original minus the key and value to be removed. In the case of mutable maps, the original map is modified and then returned. In order to use this method properly with mutable and fixed size maps the following approach must be taken:
         map = map.withoutKey("key");
         
        In the case of FixedSizeMap, a new instance will be returned by withoutKey, and any variables that previously referenced the original map will need to be redirected to reference the new instance. In the case of a FastMap or UnifiedMap, you will be replacing the reference to map with map, since FastMap and UnifiedMap will both return "this" after calling remove on themselves.
        Specified by:
        withoutKey in interface MutableMap<K,​V>
        Specified by:
        withoutKey in interface MutableMapIterable<K,​V>
        Overrides:
        withoutKey in class AbstractMutableMap<K,​V>
        See Also:
        Map.remove(Object)
      • flip

        public MutableSetMultimap<V,​K> flip()
        Description copied from interface: MapIterable
        Given a map from Domain -> Range return a multimap from Range -> Domain. We chose the name 'flip' rather than 'invert' or 'transpose' since this method does not have the property of applying twice returns the original.

        Since the keys in the input are unique, the values in the output are unique, so the return type should be a SetMultimap. However, since SetMultimap and SortedSetMultimap don't inherit from one another, SetMultimap here does not allow SortedMapIterable to have a SortedSetMultimap return. Thus, we compromise and call this Multimap, even though all implementations will be a SetMultimap or SortedSetMultimap.

        Specified by:
        flip in interface MapIterable<K,​V>
        Specified by:
        flip in interface MutableMap<K,​V>
        Specified by:
        flip in interface MutableMapIterable<K,​V>
        Specified by:
        flip in interface UnsortedMapIterable<K,​V>
        Overrides:
        flip in class AbstractMutableMap<K,​V>
      • containsKey

        public boolean containsKey​(java.lang.Object key)
        Specified by:
        containsKey in interface java.util.Map<K,​V>
        Specified by:
        containsKey in interface MapIterable<K,​V>
        See Also:
        Map.containsKey(Object)
      • containsValue

        public boolean containsValue​(java.lang.Object value)
        Specified by:
        containsValue in interface java.util.Map<K,​V>
        Specified by:
        containsValue in interface MapIterable<K,​V>
        See Also:
        Map.containsValue(Object)
      • get

        public V get​(java.lang.Object key)
        Specified by:
        get in interface java.util.Map<K,​V>
        Specified by:
        get in interface MapIterable<K,​V>
        See Also:
        Map.get(Object)
      • keySet

        public java.util.Set<K> keySet()
        Specified by:
        keySet in interface java.util.Map<K,​V>
      • values

        public java.util.Collection<V> values()
        Specified by:
        values in interface java.util.Map<K,​V>
      • entrySet

        public MutableSet<java.util.Map.Entry<K,​V>> entrySet()
        Specified by:
        entrySet in interface java.util.Map<K,​V>
      • toString

        public java.lang.String toString()
        Description copied from class: AbstractRichIterable
        Returns a string with the elements of the iterable separated by commas with spaces and enclosed in square brackets.
         Assert.assertEquals("[]", Lists.mutable.empty().toString());
         Assert.assertEquals("[1]", Lists.mutable.with(1).toString());
         Assert.assertEquals("[1, 2, 3]", Lists.mutable.with(1, 2, 3).toString());
         
        Specified by:
        toString in interface MapIterable<K,​V>
        Specified by:
        toString in interface RichIterable<K>
        Overrides:
        toString in class AbstractRichIterable<V>
        Returns:
        a string representation of this collection.
        See Also:
        AbstractCollection.toString()
      • hashCode

        public int hashCode()
        Description copied from interface: MapIterable
        Follows the same general contract as Map.hashCode().
        Specified by:
        hashCode in interface java.util.Map<K,​V>
        Specified by:
        hashCode in interface MapIterable<K,​V>
        Overrides:
        hashCode in class java.lang.Object
      • equals

        public boolean equals​(java.lang.Object other)
        Description copied from interface: MapIterable
        Follows the same general contract as Map.equals(Object).
        Specified by:
        equals in interface java.util.Map<K,​V>
        Specified by:
        equals in interface MapIterable<K,​V>
        Overrides:
        equals in class java.lang.Object
      • forEachKeyValue

        public void forEachKeyValue​(Procedure2<? super K,​? super V> procedure)
        Description copied from interface: MapIterable
        Calls the procedure with each key-value pair of the map.
             final Collection<String> collection = new ArrayList<String>();
             MutableMap<Integer, String> map = this.newMapWithKeysValues(1, "One", 2, "Two", 3, "Three");
             map.forEachKeyValue((Integer key, String value) -> collection.add(String.valueOf(key) + value));
             Verify.assertContainsAll(collection, "1One", "2Two", "3Three");
         
        Specified by:
        forEachKeyValue in interface MapIterable<K,​V>
      • forEachKey

        public void forEachKey​(Procedure<? super K> procedure)
        Description copied from interface: MapIterable
        Calls the procedure with each key of the map.
             final Collection<Integer> result = new ArrayList<Integer>();
             MutableMap<Integer, String> map = this.newMapWithKeysValues(1, "1", 2, "2", 3, "3");
             map.forEachKey(new CollectionAddProcedure<Integer>(result));
             Verify.assertContainsAll(result, 1, 2, 3);
         
        Specified by:
        forEachKey in interface MapIterable<K,​V>
        Overrides:
        forEachKey in class AbstractMapIterable<K,​V>
      • forEachValue

        public void forEachValue​(Procedure<? super V> procedure)
        Description copied from interface: MapIterable
        Calls the procedure with each value of the map.
             Set<String> result = UnifiedSet.newSet();
             MutableMap<Integer, String> map = this.newMapWithKeysValues(1, "One", 2, "Two", 3, "Three", 4, "Four");
             map.forEachValue(new CollectionAddProcedure<String>(result));
             Verify.assertSetsEqual(UnifiedSet.newSetWith("One", "Two", "Three", "Four"), result);
         
        Specified by:
        forEachValue in interface MapIterable<K,​V>
        Overrides:
        forEachValue in class AbstractMapIterable<K,​V>
      • forEachWithIndex

        public void forEachWithIndex​(ObjectIntProcedure<? super V> objectIntProcedure)
        Description copied from interface: InternalIterable
        Iterates over the iterable passing each element and the current relative int index to the specified instance of ObjectIntProcedure.

        Example using a Java 8 lambda:

         people.forEachWithIndex((Person person, int index) -> LOGGER.info("Index: " + index + " person: " + person.getName()));
         

        Example using an anonymous inner class:

         people.forEachWithIndex(new ObjectIntProcedure<Person>()
         {
             public void value(Person person, int index)
             {
                 LOGGER.info("Index: " + index + " person: " + person.getName());
             }
         });
         
        Specified by:
        forEachWithIndex in interface InternalIterable<K>
        Overrides:
        forEachWithIndex in class AbstractMapIterable<K,​V>
      • forEachWith

        public <P> void forEachWith​(Procedure2<? super V,​? super P> procedure,
                                    P parameter)
        Description copied from interface: InternalIterable
        The procedure2 is evaluated for each element in the iterable with the specified parameter provided as the second argument.

        Example using a Java 8 lambda:

         people.forEachWith((Person person, Person other) ->
             {
                 if (person.isRelatedTo(other))
                 {
                      LOGGER.info(person.getName());
                 }
             }, fred);
         

        Example using an anonymous inner class:

         people.forEachWith(new Procedure2<Person, Person>()
         {
             public void value(Person person, Person other)
             {
                 if (person.isRelatedTo(other))
                 {
                      LOGGER.info(person.getName());
                 }
             }
         }, fred);
         
        Specified by:
        forEachWith in interface InternalIterable<K>
        Overrides:
        forEachWith in class AbstractMapIterable<K,​V>
      • detect

        public Pair<K,​V> detect​(Predicate2<? super K,​? super V> predicate)
        Description copied from interface: MapIterable
        Return the first key and value of the map for which the predicate evaluates to true when they are given as arguments. The predicate will only be evaluated until such pair is found or until all the keys and values of the map have been used as arguments. That is, there may be keys and values of the map that are never used as arguments to the predicate. The result is null if predicate does not evaluate to true for any key/value combination.
         Pair<City, Person> detected =
             peopleByCity.detect((City city, Person person) -> city.getName().equals("Anytown") && person.getLastName().equals("Smith"));
         
        Specified by:
        detect in interface MapIterable<K,​V>
        Overrides:
        detect in class AbstractMutableMapIterable<K,​V>
      • getOnly

        public V getOnly()
        Description copied from interface: RichIterable
        Returns the element if the iterable has exactly one element. Otherwise, throw IllegalStateException.
        Specified by:
        getOnly in interface RichIterable<K>
        Overrides:
        getOnly in class AbstractMapIterable<K,​V>
        Returns:
        an element of an iterable.