Package org.eclipse.collections.api.map

Interface ImmutableMap<K,V>

All Superinterfaces:
ImmutableMapIterable<K,V>, InternalIterable<V>, Iterable<V>, MapIterable<K,V>, RichIterable<V>, UnsortedMapIterable<K,V>
All Known Implementing Classes:
AbstractImmutableMap, ImmutableUnifiedMap, ImmutableUnifiedMapWithHashingStrategy
public interface ImmutableMap<K,V> extends UnsortedMapIterable<K,V>, ImmutableMapIterable<K,V>
An ImmutableMap is different from a JCF Map because it has no mutating methods. It provides the read-only protocol of a JDK Map.

  • Method Details

    • newWithKeyValue

      ImmutableMap<K,V> newWithKeyValue(K key, V value)
      Specified by:
      newWithKeyValue in interface ImmutableMapIterable<K,V>

    • newWithAllKeyValues

      ImmutableMap<K,V> newWithAllKeyValues(Iterable<? extends Pair<? extends K,? extends V>> keyValues)
      Specified by:
      newWithAllKeyValues in interface ImmutableMapIterable<K,V>

    • newWithMap

      ImmutableMap<K,V> newWithMap(Map<? extends K,? extends V> map)
      Specified by:
      newWithMap in interface ImmutableMapIterable<K,V>

    • newWithMapIterable

      ImmutableMap<K,V> newWithMapIterable(MapIterable<? extends K,? extends V> mapIterable)
      Specified by:
      newWithMapIterable in interface ImmutableMapIterable<K,V>

    • newWithAllKeyValueArguments

      ImmutableMap<K,V> newWithAllKeyValueArguments(Pair<? extends K,? extends V>... keyValuePairs)
      Specified by:
      newWithAllKeyValueArguments in interface ImmutableMapIterable<K,V>

    • newWithoutKey

      ImmutableMap<K,V> newWithoutKey(K key)
      Specified by:
      newWithoutKey in interface ImmutableMapIterable<K,V>

    • newWithoutAllKeys

      ImmutableMap<K,V> newWithoutAllKeys(Iterable<? extends K> keys)
      Specified by:
      newWithoutAllKeys in interface ImmutableMapIterable<K,V>

    • toMap

      MutableMap<K,V> toMap()

    • flip

      ImmutableSetMultimap<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 ImmutableMapIterable<K,V>
      Specified by:
      flip in interface MapIterable<K,V>
      Specified by:
      flip in interface UnsortedMapIterable<K,V>

    • select

      ImmutableMap<K,V> select(Predicate2<? super K,? super V> predicate)
      Description copied from interface: MapIterable
      For each key and value of the map the predicate is evaluated, if the result of the evaluation is true, that key and value are returned in a new map. 
       MapIterable<City, Person> selected =
     peopleByCity.select((city, person) -> city.getName().equals("Anytown") && person.getLastName().equals("Smith"));
      Specified by:
      select in interface ImmutableMapIterable<K,V>
      Specified by:
      select in interface MapIterable<K,V>
      Specified by:
      select in interface UnsortedMapIterable<K,V>

    • reject

      ImmutableMap<K,V> reject(Predicate2<? super K,? super V> predicate)
      Description copied from interface: MapIterable
      For each key and value of the map the predicate is evaluated, if the result of the evaluation is false, that key and value are returned in a new map. 
       MapIterable<City, Person> rejected =
     peopleByCity.reject((city, person) -> city.getName().equals("Anytown") && person.getLastName().equals("Smith"));
      Specified by:
      reject in interface ImmutableMapIterable<K,V>
      Specified by:
      reject in interface MapIterable<K,V>
      Specified by:
      reject in interface UnsortedMapIterable<K,V>

    • tap

      ImmutableMap<K,V> tap(Procedure<? super V> procedure)
      Description copied from interface: MapIterable
      Executes the Procedure for each value of the map and returns this. 
       return peopleByCity.tap(person -> LOGGER.info(person.getName()));
      Specified by:
      tap in interface ImmutableMapIterable<K,V>
      Specified by:
      tap in interface MapIterable<K,V>
      Specified by:
      tap in interface RichIterable<K>
      Specified by:
      tap in interface UnsortedMapIterable<K,V>
      See Also:

    • select

      ImmutableBag<V> select(Predicate<? super V> predicate)
      Description copied from interface: RichIterable
      Returns all elements of the source collection that return true when evaluating the predicate. This method is also commonly called filter.

      Example using a Java 8 lambda expression: 

       RichIterable<Person> selected =
     people.select(person -> person.getAddress().getCity().equals("London"));

      Example using an anonymous inner class: 

       RichIterable<Person> selected =
     people.select(new Predicate<Person>()
     {
         public boolean accept(Person person)
         {
             return person.getAddress().getCity().equals("London");
         }
     });
      Specified by:
      select in interface ImmutableMapIterable<K,V>
      Specified by:
      select in interface RichIterable<K>
      Specified by:
      select in interface UnsortedMapIterable<K,V>

    • selectWith

      <P> ImmutableBag<V> selectWith(Predicate2<? super V,? super P> predicate, P parameter)
      Description copied from interface: RichIterable
      Similar to RichIterable.select(Predicate), except with an evaluation parameter for the second generic argument in Predicate2.

      E.g. return a Collection of Person elements where the person has an age greater than or equal to 18 years

      Example using a Java 8 lambda expression: 

       RichIterable<Person> selected =
     people.selectWith((Person person, Integer age) -> person.getAge()>= age, Integer.valueOf(18));

      Example using an anonymous inner class: 

       RichIterable<Person> selected =
     people.selectWith(new Predicate2<Person, Integer>()
     {
         public boolean accept(Person person, Integer age)
         {
             return person.getAge()>= age;
         }
     }, Integer.valueOf(18));
      Specified by:
      selectWith in interface ImmutableMapIterable<K,V>
      Specified by:
      selectWith in interface RichIterable<K>
      Specified by:
      selectWith in interface UnsortedMapIterable<K,V>
      Parameters:
      predicate - a Predicate2 to use as the select criteria
      parameter - a parameter to pass in for evaluation of the second argument P in predicate
      See Also:

    • reject

      ImmutableBag<V> reject(Predicate<? super V> predicate)
      Description copied from interface: RichIterable
      Returns all elements of the source collection that return false when evaluating of the predicate. This method is also sometimes called filterNot and is the equivalent of calling iterable.select(Predicates.not(predicate)).

      Example using a Java 8 lambda expression: 

       RichIterable<Person> rejected =
     people.reject(person -> person.person.getLastName().equals("Smith"));

      Example using an anonymous inner class: 

       RichIterable<Person> rejected =
     people.reject(new Predicate<Person>()
     {
         public boolean accept(Person person)
         {
             return person.person.getLastName().equals("Smith");
         }
     });
      Specified by:
      reject in interface ImmutableMapIterable<K,V>
      Specified by:
      reject in interface RichIterable<K>
      Specified by:
      reject in interface UnsortedMapIterable<K,V>
      Parameters:
      predicate - a Predicate to use as the reject criteria
      Returns:
      a RichIterable that contains elements that cause Predicate.accept(Object) method to evaluate to false

    • rejectWith

      <P> ImmutableBag<V> rejectWith(Predicate2<? super V,? super P> predicate, P parameter)
      Description copied from interface: RichIterable
      Similar to RichIterable.reject(Predicate), except with an evaluation parameter for the second generic argument in Predicate2.

      E.g. return a Collection of Person elements where the person has an age greater than or equal to 18 years

      Example using a Java 8 lambda expression: 

       RichIterable<Person> rejected =
     people.rejectWith((Person person, Integer age) -> person.getAge() < age, Integer.valueOf(18));

      Example using an anonymous inner class: 

       MutableList<Person> rejected =
     people.rejectWith(new Predicate2<Person, Integer>()
     {
         public boolean accept(Person person, Integer age)
         {
             return person.getAge() < age;
         }
     }, Integer.valueOf(18));
      Specified by:
      rejectWith in interface ImmutableMapIterable<K,V>
      Specified by:
      rejectWith in interface RichIterable<K>
      Specified by:
      rejectWith in interface UnsortedMapIterable<K,V>
      Parameters:
      predicate - a Predicate2 to use as the select criteria
      parameter - a parameter to pass in for evaluation of the second argument P in predicate
      See Also:

    • partition

      PartitionImmutableBag<V> partition(Predicate<? super V> predicate)
      Description copied from interface: RichIterable
      Filters a collection into a PartitionedIterable based on the evaluation of the predicate.

      Example using a Java 8 lambda expression: 

       PartitionIterable<Person> newYorkersAndNonNewYorkers =
     people.partition(person -> person.getAddress().getState().getName().equals("New York"));

      Example using an anonymous inner class: 

       PartitionIterable<Person> newYorkersAndNonNewYorkers =
     people.partition(new Predicate<Person>()
     {
         public boolean accept(Person person)
         {
             return person.getAddress().getState().getName().equals("New York");
         }
     });
      Specified by:
      partition in interface ImmutableMapIterable<K,V>
      Specified by:
      partition in interface RichIterable<K>
      Specified by:
      partition in interface UnsortedMapIterable<K,V>

    • partitionWith

      <P> PartitionImmutableBag<V> partitionWith(Predicate2<? super V,? super P> predicate, P parameter)
      Description copied from interface: RichIterable
      Filters a collection into a PartitionIterable based on the evaluation of the predicate.

      Example using a Java 8 lambda expression: 

       PartitionIterable<Person> newYorkersAndNonNewYorkers =
     people.partitionWith((Person person, String state) -> person.getAddress().getState().getName().equals(state), "New York");

      Example using an anonymous inner class: 

       PartitionIterable<Person> newYorkersAndNonNewYorkers =
     people.partitionWith(new Predicate2<Person, String>()
     {
         public boolean accept(Person person, String state)
         {
             return person.getAddress().getState().getName().equals(state);
         }
     }, "New York");
      Specified by:
      partitionWith in interface RichIterable<K>
      Specified by:
      partitionWith in interface UnsortedMapIterable<K,V>

    • selectInstancesOf

      <S> ImmutableBag<S> selectInstancesOf(Class<S> clazz)
      Description copied from interface: RichIterable
      Returns all elements of the source collection that are instances of the Class clazz. 
       RichIterable<Integer> integers =
     List.mutable.with(new Integer(0), new Long(0L), new Double(0.0)).selectInstancesOf(Integer.class);
      Specified by:
      selectInstancesOf in interface ImmutableMapIterable<K,V>
      Specified by:
      selectInstancesOf in interface RichIterable<K>
      Specified by:
      selectInstancesOf in interface UnsortedMapIterable<K,V>

    • collect

      <K2, V2> ImmutableMap<K2,V2> collect(Function2<? super K,? super V,Pair<K2,V2>> function)
      Description copied from interface: MapIterable
      For each key and value of the map the function is evaluated. The results of these evaluations are returned in a new map. The map returned will use the values projected from the function rather than the original values. 
       MapIterable<String, String> collected =
     peopleByCity.collect((City city, Person person) -> Pair.of(city.getCountry(), person.getAddress().getCity()));
      Specified by:
      collect in interface ImmutableMapIterable<K,V>
      Specified by:
      collect in interface MapIterable<K,V>
      Specified by:
      collect in interface UnsortedMapIterable<K,V>

    • collectValues

      <R> ImmutableMap<K,R> collectValues(Function2<? super K,? super V,? extends R> function)
      Description copied from interface: MapIterable
      For each key and value of the map the function is evaluated. The results of these evaluations are returned in a new map. The map returned will use the values projected from the function rather than the original values. 
       MapIterable<City, String> collected =
     peopleByCity.collectValues((City city, Person person) -> person.getFirstName() + " " + person.getLastName());
      Specified by:
      collectValues in interface ImmutableMapIterable<K,V>
      Specified by:
      collectValues in interface MapIterable<K,V>
      Specified by:
      collectValues in interface UnsortedMapIterable<K,V>

    • collect

      <VV> ImmutableBag<VV> collect(Function<? super V,? extends VV> function)
      Description copied from interface: RichIterable
      Returns a new collection with the results of applying the specified function on each element of the source collection. This method is also commonly called transform or map.

      Example using a Java 8 lambda expression: 

       RichIterable<String> names =
     people.collect(person -> person.getFirstName() + " " + person.getLastName());

      Example using an anonymous inner class: 

       RichIterable<String> names =
     people.collect(new Function<Person, String>()
     {
         public String valueOf(Person person)
         {
             return person.getFirstName() + " " + person.getLastName();
         }
     });
      Specified by:
      collect in interface RichIterable<K>
      Specified by:
      collect in interface UnsortedMapIterable<K,V>

    • collectWith

      <P, VV> ImmutableBag<VV> collectWith(Function2<? super V,? super P,? extends VV> function, P parameter)
      Description copied from interface: RichIterable
      Same as RichIterable.collect(Function) with a Function2 and specified parameter which is passed to the block.

      Example using a Java 8 lambda expression: 

       RichIterable<Integer> integers =
     Lists.mutable.with(1, 2, 3).collectWith((each, parameter) -> each + parameter, Integer.valueOf(1));

      Example using an anonymous inner class: 

       Function2<Integer, Integer, Integer> addParameterFunction =
     new Function2<Integer, Integer, Integer>()
     {
         public Integer value(Integer each, Integer parameter)
         {
             return each + parameter;
         }
     };
 RichIterable<Integer> integers =
     Lists.mutable.with(1, 2, 3).collectWith(addParameterFunction, Integer.valueOf(1));
      Specified by:
      collectWith in interface RichIterable<K>
      Specified by:
      collectWith in interface UnsortedMapIterable<K,V>
      Parameters:
      function - A Function2 to use as the collect transformation function
      parameter - A parameter to pass in for evaluation of the second argument P in function
      Returns:
      A new RichIterable that contains the transformed elements returned by Function2.value(Object, Object)
      See Also:

    • collectBoolean

      ImmutableBooleanBag collectBoolean(BooleanFunction<? super V> booleanFunction)
      Description copied from interface: RichIterable
      Returns a new primitive boolean iterable with the results of applying the specified function on each element of the source collection. This method is also commonly called transform or map.

      Example using a Java 8 lambda expression: 

       BooleanIterable licenses =
     people.collectBoolean(person -> person.hasDrivingLicense());

      Example using an anonymous inner class: 

       BooleanIterable licenses =
     people.collectBoolean(new BooleanFunction<Person>()
     {
         public boolean booleanValueOf(Person person)
         {
             return person.hasDrivingLicense();
         }
     });
      Specified by:
      collectBoolean in interface RichIterable<K>
      Specified by:
      collectBoolean in interface UnsortedMapIterable<K,V>

    • collectByte

      ImmutableByteBag collectByte(ByteFunction<? super V> byteFunction)
      Description copied from interface: RichIterable
      Returns a new primitive byte iterable with the results of applying the specified function on each element of the source collection. This method is also commonly called transform or map.

      Example using a Java 8 lambda expression: 

       ByteIterable bytes =
     people.collectByte(person -> person.getCode());

      Example using an anonymous inner class: 

       ByteIterable bytes =
     people.collectByte(new ByteFunction<Person>()
     {
         public byte byteValueOf(Person person)
         {
             return person.getCode();
         }
     });
      Specified by:
      collectByte in interface RichIterable<K>
      Specified by:
      collectByte in interface UnsortedMapIterable<K,V>

    • collectChar

      ImmutableCharBag collectChar(CharFunction<? super V> charFunction)
      Description copied from interface: RichIterable
      Returns a new primitive char iterable with the results of applying the specified function on each element of the source collection. This method is also commonly called transform or map.

      Example using a Java 8 lambda expression: 

       CharIterable chars =
     people.collectChar(person -> person.getMiddleInitial());

      Example using an anonymous inner class: 

       CharIterable chars =
     people.collectChar(new CharFunction<Person>()
     {
         public char charValueOf(Person person)
         {
             return person.getMiddleInitial();
         }
     });
      Specified by:
      collectChar in interface RichIterable<K>
      Specified by:
      collectChar in interface UnsortedMapIterable<K,V>

    • collectDouble

      ImmutableDoubleBag collectDouble(DoubleFunction<? super V> doubleFunction)
      Description copied from interface: RichIterable
      Returns a new primitive double iterable with the results of applying the specified function on each element of the source collection. This method is also commonly called transform or map.

      Example using a Java 8 lambda expression: 

       DoubleIterable doubles =
     people.collectDouble(person -> person.getMilesFromNorthPole());

      Example using an anonymous inner class: 

       DoubleIterable doubles =
     people.collectDouble(new DoubleFunction<Person>()
     {
         public double doubleValueOf(Person person)
         {
             return person.getMilesFromNorthPole();
         }
     });
      Specified by:
      collectDouble in interface RichIterable<K>
      Specified by:
      collectDouble in interface UnsortedMapIterable<K,V>

    • collectFloat

      ImmutableFloatBag collectFloat(FloatFunction<? super V> floatFunction)
      Description copied from interface: RichIterable
      Returns a new primitive float iterable with the results of applying the specified function on each element of the source collection. This method is also commonly called transform or map.

      Example using a Java 8 lambda expression: 

       FloatIterable floats =
     people.collectFloat(person -> person.getHeightInInches());

      Example using an anonymous inner class: 

       FloatIterable floats =
     people.collectFloat(new FloatFunction<Person>()
     {
         public float floatValueOf(Person person)
         {
             return person.getHeightInInches();
         }
     });
      Specified by:
      collectFloat in interface RichIterable<K>
      Specified by:
      collectFloat in interface UnsortedMapIterable<K,V>

    • collectInt

      ImmutableIntBag collectInt(IntFunction<? super V> intFunction)
      Description copied from interface: RichIterable
      Returns a new primitive int iterable with the results of applying the specified function on each element of the source collection. This method is also commonly called transform or map.

      Example using a Java 8 lambda expression: 

       IntIterable ints =
     people.collectInt(person -> person.getAge());

      Example using an anonymous inner class: 

       IntIterable ints =
     people.collectInt(new IntFunction<Person>()
     {
         public int intValueOf(Person person)
         {
             return person.getAge();
         }
     });
      Specified by:
      collectInt in interface RichIterable<K>
      Specified by:
      collectInt in interface UnsortedMapIterable<K,V>

    • collectLong

      ImmutableLongBag collectLong(LongFunction<? super V> longFunction)
      Description copied from interface: RichIterable
      Returns a new primitive long iterable with the results of applying the specified function on each element of the source collection. This method is also commonly called transform or map.

      Example using a Java 8 lambda expression: 

       LongIterable longs =
     people.collectLong(person -> person.getGuid());

      Example using an anonymous inner class: 

       LongIterable longs =
     people.collectLong(new LongFunction<Person>()
     {
         public long longValueOf(Person person)
         {
             return person.getGuid();
         }
     });
      Specified by:
      collectLong in interface RichIterable<K>
      Specified by:
      collectLong in interface UnsortedMapIterable<K,V>

    • collectShort

      ImmutableShortBag collectShort(ShortFunction<? super V> shortFunction)
      Description copied from interface: RichIterable
      Returns a new primitive short iterable with the results of applying the specified function on each element of the source collection. This method is also commonly called transform or map.

      Example using a Java 8 lambda expression: 

       ShortIterable shorts =
     people.collectShort(person -> person.getNumberOfJunkMailItemsReceivedPerMonth());

      Example using an anonymous inner class: 

       ShortIterable shorts =
     people.collectShort(new ShortFunction<Person>()
     {
         public short shortValueOf(Person person)
         {
             return person.getNumberOfJunkMailItemsReceivedPerMonth();
         }
     });
      Specified by:
      collectShort in interface RichIterable<K>
      Specified by:
      collectShort in interface UnsortedMapIterable<K,V>

    • collectIf

      <R> ImmutableBag<R> collectIf(Predicate<? super V> predicate, Function<? super V,? extends R> function)
      Description copied from interface: RichIterable
      Returns a new collection with the results of applying the specified function on each element of the source collection, but only for those elements which return true upon evaluation of the predicate. This is the optimized equivalent of calling iterable.select(predicate).collect(function).

      Example using a Java 8 lambda and method reference: 

       RichIterable<String> strings = Lists.mutable.with(1, 2, 3).collectIf(e -> e != null, Object::toString);

      Example using Predicates factory: 

       RichIterable<String> strings = Lists.mutable.with(1, 2, 3).collectIf(Predicates.notNull(), Functions.getToString());
      Specified by:
      collectIf in interface RichIterable<K>
      Specified by:
      collectIf in interface UnsortedMapIterable<K,V>

    • flatCollect

      <R> ImmutableBag<R> flatCollect(Function<? super V,? extends Iterable<R>> function)
      Description copied from interface: RichIterable
      flatCollect is a special case of RichIterable.collect(Function). With collect, when the Function returns a collection, the result is a collection of collections. flatCollect outputs a single "flattened" collection instead. This method is commonly called flatMap.

      Consider the following example where we have a Person class, and each Person has a list of Address objects. Take the following Function: 

       Function<Person, List<Address>> addressFunction = Person::getAddresses;
 RichIterable<Person> people = ...;
      Using collect returns a collection of collections of addresses. 
       RichIterable<List<Address>> addresses = people.collect(addressFunction);
      Using flatCollect returns a single flattened list of addresses. 
       RichIterable<Address> addresses = people.flatCollect(addressFunction);
      Specified by:
      flatCollect in interface RichIterable<K>
      Specified by:
      flatCollect in interface UnsortedMapIterable<K,V>
      Parameters:
      function - The Function to apply
      Returns:
      a new flattened collection produced by applying the given function

    • flatCollectWith

      default <P, R> ImmutableBag<R> flatCollectWith(Function2<? super V,? super P,? extends Iterable<R>> function, P parameter)
      Specified by:
      flatCollectWith in interface RichIterable<K>
      Specified by:
      flatCollectWith in interface UnsortedMapIterable<K,V>
      Since:
      9.2

    • zip

      @Deprecated <S> ImmutableBag<Pair<V,S>> zip(Iterable<S> that)
      Deprecated.
      in 6.0. Use OrderedIterable.zip(Iterable) instead.
      Description copied from interface: RichIterable
      Returns a RichIterable formed from this RichIterable and another RichIterable by combining corresponding elements in pairs. If one of the two RichIterables is longer than the other, its remaining elements are ignored.
      Specified by:
      zip in interface ImmutableMapIterable<K,V>
      Specified by:
      zip in interface RichIterable<K>
      Specified by:
      zip in interface UnsortedMapIterable<K,V>
      Type Parameters:
      S - the type of the second half of the returned pairs
      Parameters:
      that - The RichIterable providing the second half of each result pair
      Returns:
      A new RichIterable containing pairs consisting of corresponding elements of this RichIterable and that. The length of the returned RichIterable is the minimum of the lengths of this RichIterable and that.

    • zipWithIndex

      @Deprecated ImmutableSet<Pair<V,Integer>> zipWithIndex()
      Deprecated.
      in 6.0. Use OrderedIterable.zipWithIndex() instead.
      Description copied from interface: RichIterable
      Zips this RichIterable with its indices.
      Specified by:
      zipWithIndex in interface ImmutableMapIterable<K,V>
      Specified by:
      zipWithIndex in interface RichIterable<K>
      Specified by:
      zipWithIndex in interface UnsortedMapIterable<K,V>
      Returns:
      A new RichIterable containing pairs consisting of all elements of this RichIterable paired with their index. Indices start at 0.
      See Also:

    • groupBy

      <VV> ImmutableBagMultimap<VV,V> groupBy(Function<? super V,? extends VV> function)
      Description copied from interface: RichIterable
      For each element of the iterable, the function is evaluated and the results of these evaluations are collected into a new multimap, where the transformed value is the key and the original values are added to the same (or similar) species of collection as the source iterable.

      Example using a Java 8 method reference: 

       Multimap<String, Person> peopleByLastName =
     people.groupBy(Person::getLastName);

      Example using an anonymous inner class: 

       Multimap<String, Person> peopleByLastName =
     people.groupBy(new Function<Person, String>()
     {
         public String valueOf(Person person)
         {
             return person.getLastName();
         }
     });
      Specified by:
      groupBy in interface ImmutableMapIterable<K,V>
      Specified by:
      groupBy in interface RichIterable<K>
      Specified by:
      groupBy in interface UnsortedMapIterable<K,V>

    • groupByEach

      <VV> ImmutableBagMultimap<VV,V> groupByEach(Function<? super V,? extends Iterable<VV>> function)
      Description copied from interface: RichIterable
      Similar to RichIterable.groupBy(Function), except the result of evaluating function will return a collection of keys for each value.
      Specified by:
      groupByEach in interface ImmutableMapIterable<K,V>
      Specified by:
      groupByEach in interface RichIterable<K>
      Specified by:
      groupByEach in interface UnsortedMapIterable<K,V>

    • groupByUniqueKey

      default <V1> ImmutableMap<V1,V> groupByUniqueKey(Function<? super V,? extends V1> function)
      Description copied from interface: RichIterable
      For each element of the iterable, the function is evaluated, and the results of these evaluations are collected into a new map, where the transformed value is the key. The generated keys must each be unique, or else an exception is thrown.
      Specified by:
      groupByUniqueKey in interface ImmutableMapIterable<K,V>
      Specified by:
      groupByUniqueKey in interface RichIterable<K>
      Specified by:
      groupByUniqueKey in interface UnsortedMapIterable<K,V>
      See Also:

    • aggregateInPlaceBy

      default <KK, VV> ImmutableMap<KK,VV> aggregateInPlaceBy(Function<? super V,? extends KK> groupBy, Function0<? extends VV> zeroValueFactory, Procedure2<? super VV,? super V> mutatingAggregator)
      Description copied from interface: RichIterable
      Applies an aggregate procedure over the iterable grouping results into a Map based on the specific groupBy function. Aggregate results are required to be mutable as they will be changed in place by the procedure. A second function specifies the initial "zero" aggregate value to work with (i.e. new AtomicInteger(0)).
      Specified by:
      aggregateInPlaceBy in interface ImmutableMapIterable<K,V>
      Specified by:
      aggregateInPlaceBy in interface RichIterable<K>

    • aggregateBy

      default <KK, VV> ImmutableMap<KK,VV> aggregateBy(Function<? super V,? extends KK> groupBy, Function0<? extends VV> zeroValueFactory, Function2<? super VV,? super V,? extends VV> nonMutatingAggregator)
      Description copied from interface: RichIterable
      Applies an aggregate function over the iterable grouping results into a map based on the specific groupBy function. Aggregate results are allowed to be immutable as they will be replaced in place in the map. A second function specifies the initial "zero" aggregate value to work with (i.e. Integer.valueOf(0)).
      Specified by:
      aggregateBy in interface ImmutableMapIterable<K,V>
      Specified by:
      aggregateBy in interface RichIterable<K>

    • aggregateBy

      default <K1, V1, V2> ImmutableMap<K1,V2> aggregateBy(Function<? super K,? extends K1> keyFunction, Function<? super V,? extends V1> valueFunction, Function0<? extends V2> zeroValueFactory, Function2<? super V2,? super V1,? extends V2> nonMutatingAggregator)
      Description copied from interface: MapIterable
      Applies an aggregate function over the map grouping results into a map based on the specific key and value groupBy functions. Aggregate results are allowed to be immutable as they will be replaced in place in the map. A second function specifies the initial "zero" aggregate value to work with. 
       MapIterable<String, Interval> map = Maps.mutable.with("oneToFive", Interval.fromTo(1, 5), "sixToNine", Interval.fromTo(6, 9));

 MapIterable<String, Long> result = map.aggregateBy(
         eachKey -> {
             return eachKey.equals("oneToFive")  ? "lessThanSix" : "greaterOrEqualsToSix";
         },
         each -> each.sumOfInt(Integer::intValue),
         () -> 0L,
         (argument1, argument2) -> argument1 + argument2);

 MapIterable<String, Long> expected =
         Maps.mutable.with("lessThanSix", Interval.fromTo(1, 5).sumOfInt(Integer::intValue),
                 "greaterOrEqualsToSix", Interval.fromTo(6, 9).sumOfInt(Integer::intValue));
 Assert.assertEquals(expected, result);
      Specified by:
      aggregateBy in interface ImmutableMapIterable<K,V>
      Specified by:
      aggregateBy in interface MapIterable<K,V>

    • flipUniqueValues

      ImmutableMap<V,K> flipUniqueValues()
      Description copied from interface: MapIterable
      Return the MapIterable that is obtained by flipping the direction of this map and making the associations from value to key. 
           MapIterable<Integer, String> map = this.newMapWithKeysValues(1, "1", 2, "2", 3, "3");
     MapIterable<String, Integer> result = map.flipUniqueValues();
     Assert.assertTrue(result.equals(UnifiedMap.newWithKeysValues("1", 1, "2", 2, "3", 3)));
      Specified by:
      flipUniqueValues in interface ImmutableMapIterable<K,V>
      Specified by:
      flipUniqueValues in interface MapIterable<K,V>
      Specified by:
      flipUniqueValues in interface UnsortedMapIterable<K,V>