com.landawn.abacus.util

Class Multiset<T>

java.lang.Object

com.landawn.abacus.util.Multiset<T>

Type Parameters:

T -

All Implemented Interfaces:

java.lang.Iterable<T>

public final class Multiset<T>
extends java.lang.Object
implements java.lang.Iterable<T>

A collection that supports order-independent equality, like Set, but may have duplicate elements.

Elements of a Multiset that are equal to one another are referred to as occurrences of the same single element. The total number of occurrences of an element in a Multiset is called the count of that element (the terms "frequency" and "multiplicity" are equivalent, but not used in this API). Since the count of an element is represented as an int, a Multiset may never contain more than MutableInt#MAX_VALUE occurrences of any one element.

Since:

0.8

Author:

Haiyang Li

Constructor Summary

Constructors

Constructor and Description
Multiset()
Multiset(java.lang.Class<? extends java.util.Map> valueMapType)
Multiset(java.util.Collection<? extends T> c)
Multiset(int initialCapacity)
Multiset(Supplier<? extends java.util.Map<T,?>> mapSupplier)

Method Summary

Modifier and Type	Method and Description
<E extends java.lang.Exception> void	accept(Try.Consumer<? super Multiset<T>,E> action)
boolean	add(T e)
boolean	add(T e, int occurrences)
boolean	addAll(java.util.Collection<? extends T> c)
boolean	addAll(java.util.Collection<? extends T> c, int occurrences)
boolean	addAll(java.util.Map<? extends T,java.lang.Integer> m)
boolean	addAll(Multiset<? extends T> multiset)
int	addAndGet(T e)
int	addAndGet(T e, int occurrences)
boolean	addIfAbsent(T e)
boolean	addIfAbsent(T e, int occurrences)
Optional<Pair<java.util.List<T>,java.lang.Integer>>	allMaxOccurrences()
Optional<Pair<java.util.List<T>,java.lang.Integer>>	allMinOccurrences()
<R,E extends java.lang.Exception> R	apply(Try.Function<? super Multiset<T>,R,E> func)
OptionalDouble	averageOfOccurrences()
void	clear()
<E extends java.lang.Exception> int	compute(T key, Try.BiFunction<? super T,java.lang.Integer,java.lang.Integer,E> remappingFunction) The implementation is equivalent to performing the following steps for this Multiset:
<E extends java.lang.Exception> int	computeIfAbsent(T e, Try.Function<? super T,java.lang.Integer,E> mappingFunction) The implementation is equivalent to performing the following steps for this Multiset:
<E extends java.lang.Exception> int	computeIfPresent(T e, Try.BiFunction<? super T,java.lang.Integer,java.lang.Integer,E> remappingFunction) The implementation is equivalent to performing the following steps for this Multiset:
boolean	contains(java.lang.Object o)
boolean	containsAll(java.util.Collection<?> c)
Multiset<T>	copy()
java.util.Set<T>	elements()
EntryStream<T,java.lang.Integer>	entryStream()
boolean	equals(java.lang.Object obj)
<E extends java.lang.Exception> Multiset<T>	filter(Try.BiPredicate<? super T,java.lang.Integer,E> filter)
<E extends java.lang.Exception> Multiset<T>	filter(Try.Predicate<? super T,E> filter)
java.util.List<T>	flatten()
<E extends java.lang.Exception> void	forEach(Try.ObjIntConsumer<? super T,E> action)
static <T> Multiset<T>	from(java.util.Collection<? extends T> coll)
static <T> Multiset<T>	from(java.util.Map<? extends T,java.lang.Integer> m)
int	get(java.lang.Object e)
int	getAndAdd(T e)
int	getAndAdd(T e, int occurrences)
int	getAndRemove(java.lang.Object e)
int	getAndRemove(java.lang.Object e, int occurrences)
int	getAndSet(T e, int occurrences) The element will be removed if the specified count is 0.
int	getOrDefault(java.lang.Object e, int defaultValue)
int	hashCode()
<R,E extends java.lang.Exception> Optional<R>	ifNotEmpty(Try.Function<? super Multiset<T>,R,E> func)
boolean	isEmpty()
java.util.Iterator<T>	iterator()
Optional<Pair<T,java.lang.Integer>>	maxOccurrences()
<E extends java.lang.Exception> int	merge(T key, int value, Try.BiFunction<java.lang.Integer,java.lang.Integer,java.lang.Integer,E> remappingFunction) The implementation is equivalent to performing the following steps for this Multiset:
Optional<Pair<T,java.lang.Integer>>	minOccurrences()
int	occurrencesOf(java.lang.Object e)
static <T> Multiset<T>	of(T... a)
boolean	remove(java.lang.Object e) Remove one occurrence from the specified elements.
boolean	remove(java.lang.Object e, int occurrences) Remove the specified occurrences from the specified element.
boolean	removeAll(java.util.Collection<?> c) Removes all of this Multiset's elements that are also contained in the specified collection (optional operation).
boolean	removeAll(java.util.Collection<?> c, int occurrences) Remove the specified occurrences from the specified elements.
boolean	removeAll(java.util.Map<?,java.lang.Integer> m)
boolean	removeAll(Multiset<?> multiset)
int	removeAllOccurrences(java.lang.Object e)
<E extends java.lang.Exception> boolean	removeAllOccurrencesIf(Try.BiPredicate<? super T,? super java.lang.Integer,E> predicate)
<E extends java.lang.Exception> boolean	removeAllOccurrencesIf(Try.Predicate<? super T,E> predicate)
int	removeAndGet(java.lang.Object e)
int	removeAndGet(java.lang.Object e, int occurrences)
<E extends java.lang.Exception> boolean	removeIf(int occurrences, Try.BiPredicate<? super T,? super java.lang.Integer,E> predicate)
<E extends java.lang.Exception> boolean	removeIf(int occurrences, Try.Predicate<? super T,E> predicate)
<E extends java.lang.Exception> void	replaceAll(Try.BiFunction<? super T,? super java.lang.Integer,java.lang.Integer,E> function) The associated elements will be removed if zero or negative occurrences are returned by the specified function.
<E extends java.lang.Exception> boolean	replaceIf(Try.BiPredicate<? super T,? super java.lang.Integer,E> predicate, int newOccurrences)
<E extends java.lang.Exception> boolean	replaceIf(Try.Predicate<? super T,E> predicate, int newOccurrences)
boolean	retainAll(java.util.Collection<?> c) Retains only the elements in this collection that are contained in the specified collection (optional operation).
Multiset<T>	set(T e, int occurrences) The element will be removed if the specified count is 0.
Multiset<T>	setAll(java.util.Collection<? extends T> c, int occurrences)
Multiset<T>	setAll(java.util.Map<? extends T,java.lang.Integer> m)
Multiset<T>	setAll(Multiset<? extends T> multiset)
int	setAndGet(T e, int occurrences) The element will be removed if the specified count is 0.
int	size()
Stream<java.util.Map.Entry<T,java.lang.Integer>>	stream()
long	sumOfOccurrences()
java.lang.Object[]	toArray()
<A> A[]	toArray(A[] a)
ImmutableMap<T,java.lang.Integer>	toImmutableMap()
ImmutableMap<T,java.lang.Integer>	toImmutableMap(IntFunction<? extends java.util.Map<T,java.lang.Integer>> mapSupplier)
java.util.Map<T,java.lang.Integer>	toMap()
<M extends java.util.Map<T,java.lang.Integer>> M	toMap(IntFunction<M> supplier)
java.util.Map<T,java.lang.Integer>	toMapSortedByKey(java.util.Comparator<? super T> cmp)
java.util.Map<T,java.lang.Integer>	toMapSortedByOccurrences()
java.util.Map<T,java.lang.Integer>	toMapSortedByOccurrences(java.util.Comparator<? super java.lang.Integer> cmp)
java.lang.String	toString()

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface java.lang.Iterable

forEach, spliterator

Constructor Detail

Multiset

public Multiset()

Multiset

public Multiset(int initialCapacity)

Multiset

public Multiset(java.lang.Class<? extends java.util.Map> valueMapType)

Multiset

public Multiset(Supplier<? extends java.util.Map<T,?>> mapSupplier)

Multiset

public Multiset(java.util.Collection<? extends T> c)

Method Detail

of

@SafeVarargs
public static <T> Multiset<T> of(T... a)

from

public static <T> Multiset<T> from(java.util.Collection<? extends T> coll)

from

public static <T> Multiset<T> from(java.util.Map<? extends T,java.lang.Integer> m)

get

public int get(java.lang.Object e)

Parameters:

e -

Returns:

the occurrences of the specified object. zero is returned if it's not in this set.

getOrDefault

public int getOrDefault(java.lang.Object e,
                        int defaultValue)

Parameters:

e -

defaultValue -

Returns:

the occurrences of the specified object. the specified defaultValue is returned if it's not in this set.

getAndSet

public int getAndSet(T e,
                     int occurrences)

The element will be removed if the specified count is 0.

Parameters:

e -

occurrences -

Returns:

setAndGet

public int setAndGet(T e,
                     int occurrences)

The element will be removed if the specified count is 0.

Parameters:

e -

occurrences -

Returns:

set

public Multiset<T> set(T e,
                       int occurrences)

The element will be removed if the specified count is 0.

Parameters:

e -

occurrences -

Returns:

this Multiset.

Throws:

java.lang.IllegalArgumentException - if the occurrences of element is less than 0

setAll

public Multiset<T> setAll(java.util.Collection<? extends T> c,
                          int occurrences)

setAll

public Multiset<T> setAll(java.util.Map<? extends T,java.lang.Integer> m)
                   throws java.lang.IllegalArgumentException

Parameters:

m -

Returns:

this Multiset.

Throws:

java.lang.IllegalArgumentException - if the occurrences of element is less than 0.

setAll

public Multiset<T> setAll(Multiset<? extends T> multiset)
                   throws java.lang.IllegalArgumentException

Parameters:

m -

Returns:

this Multiset.

Throws:

java.lang.IllegalArgumentException - if the occurrences of element is less than 0.

occurrencesOf

public int occurrencesOf(java.lang.Object e)

minOccurrences

public Optional<Pair<T,java.lang.Integer>> minOccurrences()

maxOccurrences

public Optional<Pair<T,java.lang.Integer>> maxOccurrences()

allMinOccurrences

public Optional<Pair<java.util.List<T>,java.lang.Integer>> allMinOccurrences()

allMaxOccurrences

public Optional<Pair<java.util.List<T>,java.lang.Integer>> allMaxOccurrences()

sumOfOccurrences

public long sumOfOccurrences()

Returns:

Throws:

java.lang.ArithmeticException - if total occurrences overflows the maximum value of int.

averageOfOccurrences

public OptionalDouble averageOfOccurrences()

add

public boolean add(T e)
            throws java.lang.IllegalArgumentException

Parameters:

e -

Returns:

always true

Throws:

java.lang.IllegalArgumentException - if the occurrences of element after this operation is bigger than Integer.MAX_VALUE.

add

public boolean add(T e,
                   int occurrences)
            throws java.lang.IllegalArgumentException

Parameters:

e -

occurrences -

Returns:

true if the specified occurrences is bigger than 0.

Throws:

java.lang.IllegalArgumentException - if the occurrences of element after this operation is bigger than Integer.MAX_VALUE.

addIfAbsent

public boolean addIfAbsent(T e)
                    throws java.lang.IllegalArgumentException

Parameters:

e -

Returns:

true if the specified element is absent.

Throws:

java.lang.IllegalArgumentException

addIfAbsent

public boolean addIfAbsent(T e,
                           int occurrences)
                    throws java.lang.IllegalArgumentException

Parameters:

e -

occurrences -

Returns:

true if the specified element is absent and occurrences is bigger than 0.

Throws:

java.lang.IllegalArgumentException

addAndGet

public int addAndGet(T e)

addAndGet

public int addAndGet(T e,
                     int occurrences)

getAndAdd

public int getAndAdd(T e)

getAndAdd

public int getAndAdd(T e,
                     int occurrences)

addAll

public boolean addAll(java.util.Collection<? extends T> c)
               throws java.lang.IllegalArgumentException

Parameters:

c -

Throws:

java.lang.IllegalArgumentException - if the occurrences of element after this operation is bigger than Integer.MAX_VALUE.

addAll

public boolean addAll(java.util.Collection<? extends T> c,
                      int occurrences)
               throws java.lang.IllegalArgumentException

Parameters:

c -

occurrences -

Throws:

java.lang.IllegalArgumentException - if the occurrences of element after this operation is bigger than Integer.MAX_VALUE.

addAll

public boolean addAll(java.util.Map<? extends T,java.lang.Integer> m)
               throws java.lang.IllegalArgumentException

Parameters:

m -

Throws:

java.lang.IllegalArgumentException - if the occurrences of element after this operation is bigger than Integer.MAX_VALUE.

addAll

public boolean addAll(Multiset<? extends T> multiset)
               throws java.lang.IllegalArgumentException

Parameters:

m -

Throws:

java.lang.IllegalArgumentException - if the occurrences of element is less than 0.

contains

public boolean contains(java.lang.Object o)

containsAll

public boolean containsAll(java.util.Collection<?> c)

remove

public boolean remove(java.lang.Object e)

Remove one occurrence from the specified elements. The element will be removed from this Multiset if the occurrences equals to or less than 0 after the operation.

Parameters:

e -

occurrences -

Returns:

remove

public boolean remove(java.lang.Object e,
                      int occurrences)

Remove the specified occurrences from the specified element. The element will be removed from this Multiset if the occurrences equals to or less than 0 after the operation.

Parameters:

e -

occurrences -

Returns:

removeAndGet

public int removeAndGet(java.lang.Object e)

removeAndGet

public int removeAndGet(java.lang.Object e,
                        int occurrences)

getAndRemove

public int getAndRemove(java.lang.Object e)

getAndRemove

public int getAndRemove(java.lang.Object e,
                        int occurrences)

removeAllOccurrences

public int removeAllOccurrences(java.lang.Object e)

Parameters:

e -

Returns:

the occurrences of the specified element before it's removed.

removeAllOccurrencesIf

public <E extends java.lang.Exception> boolean removeAllOccurrencesIf(Try.Predicate<? super T,E> predicate)
                                                               throws E extends java.lang.Exception

Throws:

E extends java.lang.Exception

removeAllOccurrencesIf

public <E extends java.lang.Exception> boolean removeAllOccurrencesIf(Try.BiPredicate<? super T,? super java.lang.Integer,E> predicate)
                                                               throws E extends java.lang.Exception

Throws:

E extends java.lang.Exception

removeIf

public <E extends java.lang.Exception> boolean removeIf(int occurrences,
                                                        Try.Predicate<? super T,E> predicate)
                                                 throws E extends java.lang.Exception

Throws:

E extends java.lang.Exception

removeIf

public <E extends java.lang.Exception> boolean removeIf(int occurrences,
                                                        Try.BiPredicate<? super T,? super java.lang.Integer,E> predicate)
                                                 throws E extends java.lang.Exception

Throws:

E extends java.lang.Exception

removeAll

public boolean removeAll(java.util.Collection<?> c)

Removes all of this Multiset's elements that are also contained in the specified collection (optional operation). After this call returns, this Multiset will contain no elements in common with the specified collection. This method ignores how often any element might appear in c, and only cares whether or not an element appears at all.

Parameters:

c -

Returns:

true if this set changed as a result of the call

See Also:

Collection.removeAll(Collection)

removeAll

public boolean removeAll(java.util.Collection<?> c,
                         int occurrences)

Remove the specified occurrences from the specified elements. The elements will be removed from this set if the occurrences equals to or less than 0 after the operation.

Parameters:

c -

occurrences - the occurrences to remove if the element is in the specified collection c.

Returns:

true if this set changed as a result of the call

removeAll

public boolean removeAll(java.util.Map<?,java.lang.Integer> m)

Parameters:

m -

Returns:

removeAll

public boolean removeAll(Multiset<?> multiset)
                  throws java.lang.IllegalArgumentException

Parameters:

m -

Throws:

java.lang.IllegalArgumentException

replaceIf

public <E extends java.lang.Exception> boolean replaceIf(Try.Predicate<? super T,E> predicate,
                                                         int newOccurrences)
                                                  throws E extends java.lang.Exception

Throws:

E extends java.lang.Exception

replaceIf

public <E extends java.lang.Exception> boolean replaceIf(Try.BiPredicate<? super T,? super java.lang.Integer,E> predicate,
                                                         int newOccurrences)
                                                  throws E extends java.lang.Exception

Throws:

E extends java.lang.Exception

replaceAll

public <E extends java.lang.Exception> void replaceAll(Try.BiFunction<? super T,? super java.lang.Integer,java.lang.Integer,E> function)
                                                throws E extends java.lang.Exception

The associated elements will be removed if zero or negative occurrences are returned by the specified function.

Parameters:

function -

Throws:

E extends java.lang.Exception

retainAll

public boolean retainAll(java.util.Collection<?> c)

Retains only the elements in this collection that are contained in the specified collection (optional operation). In other words, removes from this collection all of its elements that are not contained in the specified collection.

Parameters:

c -

Returns:

true if this set changed as a result of the call

See Also:

Collection.retainAll(Collection)

copy

public Multiset<T> copy()

elements

public java.util.Set<T> elements()

size

public int size()

isEmpty

public boolean isEmpty()

clear

public void clear()

iterator

public java.util.Iterator<T> iterator()

Specified by:

iterator in interface java.lang.Iterable<T>

toArray

public java.lang.Object[] toArray()

toArray

public <A> A[] toArray(A[] a)

toMap

public java.util.Map<T,java.lang.Integer> toMap()

toMap

public <M extends java.util.Map<T,java.lang.Integer>> M toMap(IntFunction<M> supplier)

toMapSortedByOccurrences

public java.util.Map<T,java.lang.Integer> toMapSortedByOccurrences()

toMapSortedByOccurrences

public java.util.Map<T,java.lang.Integer> toMapSortedByOccurrences(java.util.Comparator<? super java.lang.Integer> cmp)

toMapSortedByKey

public java.util.Map<T,java.lang.Integer> toMapSortedByKey(java.util.Comparator<? super T> cmp)

toImmutableMap

public ImmutableMap<T,java.lang.Integer> toImmutableMap()

toImmutableMap

public ImmutableMap<T,java.lang.Integer> toImmutableMap(IntFunction<? extends java.util.Map<T,java.lang.Integer>> mapSupplier)

flatten

public java.util.List<T> flatten()

Returns:

a list with all elements, each of them is repeated with the occurrences in this Multiset

filter

public <E extends java.lang.Exception> Multiset<T> filter(Try.Predicate<? super T,E> filter)
                                                   throws E extends java.lang.Exception

Throws:

E extends java.lang.Exception

filter

public <E extends java.lang.Exception> Multiset<T> filter(Try.BiPredicate<? super T,java.lang.Integer,E> filter)
                                                   throws E extends java.lang.Exception

Throws:

E extends java.lang.Exception

forEach

public <E extends java.lang.Exception> void forEach(Try.ObjIntConsumer<? super T,E> action)
                                             throws E extends java.lang.Exception

Throws:

E extends java.lang.Exception

computeIfAbsent

public <E extends java.lang.Exception> int computeIfAbsent(T e,
                                                           Try.Function<? super T,java.lang.Integer,E> mappingFunction)
                                                    throws E extends java.lang.Exception

The implementation is equivalent to performing the following steps for this Multiset:

 final int oldValue = get(e);
 
 if (oldValue > 0) {
     return oldValue;
 }
 
 final int newValue = mappingFunction.apply(e);
 
 if (newValue > 0) {
     set(e, newValue);
 }
 
 return newValue;
 

Parameters:

e -

mappingFunction -

Returns:

Throws:

E extends java.lang.Exception

computeIfPresent

public <E extends java.lang.Exception> int computeIfPresent(T e,
                                                            Try.BiFunction<? super T,java.lang.Integer,java.lang.Integer,E> remappingFunction)
                                                     throws E extends java.lang.Exception

The implementation is equivalent to performing the following steps for this Multiset:

 
 final int oldValue = get(e);
 
 if (oldValue == 0) {
     return oldValue;
 }
 
 final int newValue = remappingFunction.apply(e, oldValue);
 
 if (newValue > 0) {
     set(e, newValue);
 } else {
     remove(e);
 }
 
 return newValue;
 

Parameters:

e -

remappingFunction -

Returns:

Throws:

E extends java.lang.Exception

compute

public <E extends java.lang.Exception> int compute(T key,
                                                   Try.BiFunction<? super T,java.lang.Integer,java.lang.Integer,E> remappingFunction)
                                            throws E extends java.lang.Exception

The implementation is equivalent to performing the following steps for this Multiset:

 final int oldValue = get(key);
 final int newValue = remappingFunction.apply(key, oldValue);
 
 if (newValue > 0) {
     set(key, newValue);
 } else {
     if (oldValue > 0) {
         remove(key);
     }
 }
 
 return newValue;
 

Parameters:

key -

remappingFunction -

Returns:

Throws:

E extends java.lang.Exception

merge

public <E extends java.lang.Exception> int merge(T key,
                                                 int value,
                                                 Try.BiFunction<java.lang.Integer,java.lang.Integer,java.lang.Integer,E> remappingFunction)
                                          throws E extends java.lang.Exception

The implementation is equivalent to performing the following steps for this Multiset:

 int oldValue = get(key);
 int newValue = (oldValue == 0) ? value : remappingFunction.apply(oldValue, value);
 
 if (newValue > 0) {
     set(key, newValue);
 } else {
     if (oldValue > 0) {
         remove(key);
     }
 }
 
 return newValue;
 

Parameters:

key -

value -

remappingFunction -

Returns:

Throws:

E extends java.lang.Exception

stream

public Stream<java.util.Map.Entry<T,java.lang.Integer>> stream()

entryStream

public EntryStream<T,java.lang.Integer> entryStream()

ifNotEmpty

public <R,E extends java.lang.Exception> Optional<R> ifNotEmpty(Try.Function<? super Multiset<T>,R,E> func)
                                                         throws E extends java.lang.Exception

Throws:

E extends java.lang.Exception

apply

public <R,E extends java.lang.Exception> R apply(Try.Function<? super Multiset<T>,R,E> func)
                                          throws E extends java.lang.Exception

Throws:

E extends java.lang.Exception

accept

public <E extends java.lang.Exception> void accept(Try.Consumer<? super Multiset<T>,E> action)
                                            throws E extends java.lang.Exception

Throws:

E extends java.lang.Exception

hashCode

public int hashCode()

Overrides:

hashCode in class java.lang.Object

equals

public boolean equals(java.lang.Object obj)

Overrides:

equals in class java.lang.Object

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object