Package org.eclipse.collections.api.bag

Interface MutableBagIterable<T>

    • Method Detail

      • addOccurrences

        int addOccurrences​(T item,
                   int occurrences)
        Add number of occurrences for an item. If the item does not exist, then the item is added to the bag.

        For Example: 

         MutableBagIterable<String> names = Bags.mutable.of("A", "B", "B");
 Assert.assertEquals(4, names.addOccurrences("A", 3));
        Returns:
        updated number of occurrences.
        Throws:
        IllegalArgumentException - if occurrences are less than 0.

      • removeOccurrences

        boolean removeOccurrences​(Object item,
                          int occurrences)

      • setOccurrences

        boolean setOccurrences​(T item,
                       int occurrences)

      • select

        MutableBagIterable<T> select​(Predicate<? super T> 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"));
        Specified by:
        select in interface Bag<T>
        Specified by:
        select in interface MutableCollection<T>
        Specified by:
        select in interface RichIterable<T>

      • reject

        MutableBagIterable<T> reject​(Predicate<? super T> 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"));
        Specified by:
        reject in interface Bag<T>
        Specified by:
        reject in interface MutableCollection<T>
        Specified by:
        reject in interface RichIterable<T>
        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

      • partition

        PartitionMutableBagIterable<T> partition​(Predicate<? super T> 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"));
        Specified by:
        partition in interface Bag<T>
        Specified by:
        partition in interface MutableCollection<T>
        Specified by:
        partition in interface RichIterable<T>

      • partitionWith

        <P> PartitionMutableBagIterable<T> partitionWith​(Predicate2<? super T,​? 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");
        Specified by:
        partitionWith in interface Bag<T>
        Specified by:
        partitionWith in interface MutableCollection<T>
        Specified by:
        partitionWith in interface RichIterable<T>

      • groupBy

        <V> MutableBagIterableMultimap<V,​T> groupBy​(Function<? super T,​? extends V> 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);
        Specified by:
        groupBy in interface Bag<T>
        Specified by:
        groupBy in interface MutableCollection<T>
        Specified by:
        groupBy in interface RichIterable<T>

      • selectDuplicates

        default MutableBagIterable<T> selectDuplicates()
        Description copied from interface: Bag
        Returns all elements of the bag that have more than one occurrence.
        Specified by:
        selectDuplicates in interface Bag<T>
        Since:
        9.2

      • selectUnique

        MutableSetIterable<T> selectUnique()
        Description copied from interface: Bag
        Returns a set containing all elements of the bag that have exactly one occurrence.
        Specified by:
        selectUnique in interface Bag<T>
        Since:
        9.2

      • topOccurrences

        MutableList<ObjectIntPair<T>> topOccurrences​(int count)
        Description copied from interface: Bag
        Returns the count most frequently occurring items. In the event of a tie, all the items with the number of occurrences that match the occurrences of the last item will be returned.
        Specified by:
        topOccurrences in interface Bag<T>
        Since:
        6.0

      • bottomOccurrences

        MutableList<ObjectIntPair<T>> bottomOccurrences​(int count)
        Description copied from interface: Bag
        Returns the count least frequently occurring items. In the event of a tie, all of the items with the number of occurrences that match the occurrences of the last item will be returned.
        Specified by:
        bottomOccurrences in interface Bag<T>
        Since:
        6.0

      • with

        default MutableBagIterable<T> with​(T element)
        Description copied from interface: MutableCollection
        This method allows mutable and fixed size collections the ability to add elements to their existing elements. In order to support fixed size a new instance of a collection would have to be returned taking the elements of the original collection and appending the new element to form the new collection. In the case of mutable collections, the original collection is modified, and is returned. In order to use this method properly with mutable and fixed size collections the following approach must be taken: 
         MutableCollection<String> list = list.with("1");
 list = list.with("2");
 return list;
        In the case of FixedSizeCollection a new instance of MutableCollection will be returned by with, and any variables that previously referenced the original collection will need to be redirected to reference the new instance. For other MutableCollection types you will replace the reference to collection with the same collection, since the instance will return "this" after calling add on itself.
        Specified by:
        with in interface MutableCollection<T>
        See Also:
        Collection.add(Object)

      • without

        default MutableBagIterable<T> without​(T element)
        Description copied from interface: MutableCollection
        This method allows mutable and fixed size collections the ability to remove elements from their existing elements. In order to support fixed size a new instance of a collection would have to be returned containing the elements that would be left from the original collection after calling remove. In the case of mutable collections, the original collection is modified, and is returned. In order to use this method properly with mutable and fixed size collections the following approach must be taken: 
         MutableCollection<String> list = list.without("1");
 list = list.without("2");
 return list;
        In the case of FixedSizeCollection a new instance of MutableCollection will be returned by without, and any variables that previously referenced the original collection will need to be redirected to reference the new instance. For other MutableCollection types you will replace the reference to collection with the same collection, since the instance will return "this" after calling remove on itself.
        Specified by:
        without in interface MutableCollection<T>
        See Also:
        Collection.remove(Object)

      • withAll

        default MutableBagIterable<T> withAll​(Iterable<? extends T> elements)
        Description copied from interface: MutableCollection
        This method allows mutable and fixed size collections the ability to add multiple elements to their existing elements. In order to support fixed size a new instance of a collection would have to be returned taking the elements of the original collection and appending the new elements to form the new collection. In the case of mutable collections, the original collection is modified, and is returned. In order to use this method properly with mutable and fixed size collections the following approach must be taken: 
         MutableCollection<String> list = list.withAll(FastList.newListWith("1", "2"));
        In the case of FixedSizeCollection a new instance of MutableCollection will be returned by withAll, and any variables that previously referenced the original collection will need to be redirected to reference the new instance. For other MutableCollection types you will replace the reference to collection with the same collection, since the instance will return "this" after calling addAll on itself.
        Specified by:
        withAll in interface MutableCollection<T>
        See Also:
        Collection.addAll(Collection)

      • withoutAll

        default MutableBagIterable<T> withoutAll​(Iterable<? extends T> elements)
        Description copied from interface: MutableCollection
        This method allows mutable and fixed size collections the ability to remove multiple elements from their existing elements. In order to support fixed size a new instance of a collection would have to be returned containing the elements that would be left from the original collection after calling removeAll. In the case of mutable collections, the original collection is modified, and is returned. In order to use this method properly with mutable and fixed size collections the following approach must be taken: 
         MutableCollection<String> list = list.withoutAll(FastList.newListWith("1", "2"));
        In the case of FixedSizeCollection a new instance of MutableCollection will be returned by withoutAll, and any variables that previously referenced the original collection will need to be redirected to reference the new instance. For other MutableCollection types you will replace the reference to collection with the same collection, since the instance will return "this" after calling removeAll on itself.
        Specified by:
        withoutAll in interface MutableCollection<T>
        See Also:
        Collection.removeAll(Collection)

      • collectWithOccurrences

        <V> RichIterable<V> collectWithOccurrences​(ObjectIntToObjectFunction<? super T,​? extends V> function)
        Description copied from interface: Bag
        Iterates over the unique elements and their occurrences and collects the results of applying the specified function.
        Specified by:
        collectWithOccurrences in interface Bag<T>