@GwtCompatible(emulated=true)
public final class TreeMultiset<E>
extends java.util.AbstractCollection<E>
implements java.io.Serializable
Comparator. In all cases, this implementation uses
Comparable.compareTo(T) or Comparator.compare(T, T) instead of Object.equals(java.lang.Object) to
determine equivalence of instances.
Warning: The comparison must be consistent with equals as explained by the
Comparable class specification. Otherwise, the resulting multiset will violate the
Collection contract, which is specified in terms of Object.equals(java.lang.Object).
See the Guava User Guide article on
Multiset.
Multiset.Entry<E>| Modifier and Type | Method and Description |
|---|---|
boolean |
add(E element)
Adds a single occurrence of the specified element to this multiset.
|
int |
add(E element,
int occurrences)
Adds a number of occurrences of an element to this multiset.
|
boolean |
addAll(java.util.Collection<? extends E> elementsToAdd) |
void |
clear() |
java.util.Comparator<? super E> |
comparator()
Returns the comparator that orders this multiset, or
Ordering.natural() if the natural ordering of the elements is used. |
boolean |
contains(java.lang.Object element)
Determines whether this multiset contains the specified element.
|
int |
count(java.lang.Object element)
Returns the number of occurrences of an element in this multiset (the
count of the element).
|
static <E extends java.lang.Comparable> |
create()
Creates a new, empty multiset, sorted according to the elements' natural order.
|
static <E> TreeMultiset<E> |
create(java.util.Comparator<? super E> comparator)
Creates a new, empty multiset, sorted according to the specified comparator.
|
static <E extends java.lang.Comparable> |
create(java.lang.Iterable<? extends E> elements)
Creates an empty multiset containing the given initial elements, sorted according to the
elements' natural order.
|
SortedMultiset<E> |
descendingMultiset()
Returns a descending view of this multiset.
|
java.util.NavigableSet<E> |
elementSet()
Returns the set of distinct elements contained in this multiset.
|
java.util.Set<Multiset.Entry<E>> |
entrySet()
Returns a view of the contents of this multiset, grouped into
Multiset.Entry instances, each providing an element of the multiset and
the count of that element. |
boolean |
equals(java.lang.Object object)
Compares the specified object with this multiset for equality.
|
Multiset.Entry<E> |
firstEntry()
Returns the entry of the first element in this multiset, or
null if
this multiset is empty. |
int |
hashCode()
Returns the hash code for this multiset.
|
SortedMultiset<E> |
headMultiset(E upperBound,
BoundType boundType)
Returns a view of this multiset restricted to the elements less than
upperBound, optionally including upperBound itself. |
boolean |
isEmpty() |
java.util.Iterator<E> |
iterator() |
Multiset.Entry<E> |
lastEntry()
Returns the entry of the last element in this multiset, or
null if
this multiset is empty. |
Multiset.Entry<E> |
pollFirstEntry()
Returns and removes the entry associated with the lowest element in this
multiset, or returns
null if this multiset is empty. |
Multiset.Entry<E> |
pollLastEntry()
Returns and removes the entry associated with the greatest element in this
multiset, or returns
null if this multiset is empty. |
boolean |
remove(java.lang.Object element)
Removes a single occurrence of the specified element from this
multiset, if present.
|
int |
remove(java.lang.Object element,
int occurrences)
Removes a number of occurrences of the specified element from this
multiset.
|
boolean |
removeAll(java.util.Collection<?> elementsToRemove) |
boolean |
retainAll(java.util.Collection<?> elementsToRetain) |
int |
setCount(E element,
int count)
Adds or removes the necessary occurrences of an element such that the
element attains the desired count.
|
boolean |
setCount(E element,
int oldCount,
int newCount)
Conditionally sets the count of an element to a new value, as described in
Multiset.setCount(Object, int), provided that the element has the expected
current count. |
int |
size() |
SortedMultiset<E> |
subMultiset(E fromElement,
BoundType fromBoundType,
E toElement,
BoundType toBoundType)
Returns a view of this multiset restricted to the range between
lowerBound and upperBound. |
SortedMultiset<E> |
tailMultiset(E lowerBound,
BoundType boundType)
Returns a view of this multiset restricted to the elements greater than
lowerBound, optionally including lowerBound itself. |
java.lang.String |
toString() |
clone, finalize, getClass, notify, notifyAll, wait, wait, waititeratorpublic static <E extends java.lang.Comparable> TreeMultiset<E> create()
Comparable interface. Furthermore, all
such elements must be mutually comparable: e1.compareTo(e2) must not throw a
ClassCastException for any elements e1 and e2 in the multiset. If the
user attempts to add an element to the multiset that violates this constraint (for example,
the user attempts to add a string element to a set whose elements are integers), the
add(Object) call will throw a ClassCastException.
The type specification is <E extends Comparable>, instead of the more specific
<E extends Comparable<? super E>>, to support classes defined without generics.
public static <E> TreeMultiset<E> create(@Nullable java.util.Comparator<? super E> comparator)
comparator.compare(e1,
e2) must not throw a ClassCastException for any elements e1 and e2 in
the multiset. If the user attempts to add an element to the multiset that violates this
constraint, the add(Object) call will throw a ClassCastException.comparator - the comparator that will be used to sort this multiset. A null value indicates that
the elements' natural ordering should be used.public static <E extends java.lang.Comparable> TreeMultiset<E> create(java.lang.Iterable<? extends E> elements)
This implementation is highly efficient when elements is itself a Multiset.
The type specification is <E extends Comparable>, instead of the more specific
<E extends Comparable<? super E>>, to support classes defined without generics.
public int size()
size in interface java.util.Collection<E>public int count(@Nullable
java.lang.Object element)
MultisetObject.equals(java.lang.Object)-based
multiset, this gives the same result as Collections.frequency(java.util.Collection<?>, java.lang.Object)
(which would presumably perform more poorly).
Note: the utility method Iterables.frequency(java.lang.Iterable<?>, java.lang.Object) generalizes
this operation; it correctly delegates to this method when dealing with a
multiset, but it can also accept any other iterable type.
public int add(@Nullable
E element,
int occurrences)
Multisetoccurrences == 1, this method has the identical effect to Multiset.add(Object). This method is functionally equivalent (except in the case
of overflow) to the call addAll(Collections.nCopies(element,
occurrences)), which would presumably perform much more poorly.add in interface Multiset<E>element - the element to add occurrences of; may be null only if
explicitly allowed by the implementationoccurrences - the number of occurrences of the element to add. May be
zero, in which case no change will be made.public int remove(@Nullable
java.lang.Object element,
int occurrences)
Multisetoccurrences == 1, this is functionally equivalent to the call
remove(element).remove in interface Multiset<E>element - the element to conditionally remove occurrences ofoccurrences - the number of occurrences of the element to remove. May
be zero, in which case no change will be made.public int setCount(@Nullable
E element,
int count)
MultisetsetCount in interface Multiset<E>element - the element to add or remove occurrences of; may be null
only if explicitly allowed by the implementationcount - the desired count of the element in this multisetpublic boolean setCount(@Nullable
E element,
int oldCount,
int newCount)
MultisetMultiset.setCount(Object, int), provided that the element has the expected
current count. If the current count is not oldCount, no change is
made.setCount in interface Multiset<E>element - the element to conditionally set the count of; may be null
only if explicitly allowed by the implementationoldCount - the expected present count of the element in this multisetnewCount - the desired count of the element in this multisettrue if the condition for modification was met. This
implies that the multiset was indeed modified, unless
oldCount == newCount.public SortedMultiset<E> headMultiset(@Nullable E upperBound, BoundType boundType)
SortedMultisetupperBound, optionally including upperBound itself. The
returned multiset is a view of this multiset, so changes to one will be
reflected in the other. The returned multiset supports all operations that
this multiset supports.
The returned multiset will throw an IllegalArgumentException on
attempts to add elements outside its range.
headMultiset in interface SortedMultiset<E>public SortedMultiset<E> tailMultiset(@Nullable E lowerBound, BoundType boundType)
SortedMultisetlowerBound, optionally including lowerBound itself. The
returned multiset is a view of this multiset, so changes to one will be
reflected in the other. The returned multiset supports all operations that
this multiset supports.
The returned multiset will throw an IllegalArgumentException on
attempts to add elements outside its range.
tailMultiset in interface SortedMultiset<E>public java.util.NavigableSet<E> elementSet()
MultisetIf the element set supports any removal operations, these necessarily cause all occurrences of the removed element(s) to be removed from the multiset. Implementations are not expected to support the add operations, although this is possible.
A common use for the element set is to find the number of distinct
elements in the multiset: elementSet().size().
elementSet in interface Multiset<E>elementSet in interface SortedMultiset<E>public java.util.Comparator<? super E> comparator()
SortedMultisetOrdering.natural() if the natural ordering of the elements is used.comparator in interface SortedMultiset<E>public Multiset.Entry<E> firstEntry()
SortedMultisetnull if
this multiset is empty.firstEntry in interface SortedMultiset<E>public Multiset.Entry<E> lastEntry()
SortedMultisetnull if
this multiset is empty.lastEntry in interface SortedMultiset<E>public Multiset.Entry<E> pollFirstEntry()
SortedMultisetnull if this multiset is empty.pollFirstEntry in interface SortedMultiset<E>public Multiset.Entry<E> pollLastEntry()
SortedMultisetnull if this multiset is empty.pollLastEntry in interface SortedMultiset<E>public SortedMultiset<E> subMultiset(@Nullable E fromElement, BoundType fromBoundType, @Nullable E toElement, BoundType toBoundType)
SortedMultisetlowerBound and upperBound. The returned multiset is a view
of this multiset, so changes to one will be reflected in the other. The
returned multiset supports all operations that this multiset supports.
The returned multiset will throw an IllegalArgumentException on
attempts to add elements outside its range.
This method is equivalent to
tailMultiset(lowerBound, lowerBoundType).headMultiset(upperBound,
upperBoundType).
subMultiset in interface SortedMultiset<E>public SortedMultiset<E> descendingMultiset()
SortedMultisetdescendingMultiset in interface SortedMultiset<E>public boolean isEmpty()
isEmpty in interface java.util.Collection<E>isEmpty in class java.util.AbstractCollection<E>public boolean contains(@Nullable
java.lang.Object element)
MultisetThis method refines Collection.contains(java.lang.Object) to further specify that
it may not throw an exception in response to element being
null or of the wrong type.
public java.util.Iterator<E> iterator()
MultisetElements that occur multiple times in the multiset will appear multiple times in this iterator, though not necessarily sequentially.
public boolean add(@Nullable
E element)
MultisetThis method refines Collection.add(E), which only ensures
the presence of the element, to further specify that a successful call must
always increment the count of the element, and the overall size of the
collection, by one.
add in interface java.util.Collection<E>add in interface Multiset<E>add in class java.util.AbstractCollection<E>element - the element to add one occurrence of; may be null only if
explicitly allowed by the implementationtrue always, since this call is required to modify the
multiset, unlike other Collection typespublic boolean remove(@Nullable
java.lang.Object element)
MultisetThis method refines Collection.remove(java.lang.Object) to further specify that it
may not throw an exception in response to element being null
or of the wrong type.
public boolean addAll(java.util.Collection<? extends E> elementsToAdd)
This implementation is highly efficient when elementsToAdd
is itself a Multiset.
addAll in interface java.util.Collection<E>addAll in class java.util.AbstractCollection<E>public boolean removeAll(java.util.Collection<?> elementsToRemove)
MultisetNote: This method ignores how often any element might appear in
c, and only cares whether or not an element appears at all.
If you wish to remove one occurrence in this multiset for every occurrence
in c, see Multisets.removeOccurrences(Multiset, Multiset).
This method refines Collection.removeAll(java.util.Collection<?>) to further specify that
it may not throw an exception in response to any of elements
being null or of the wrong type.
public boolean retainAll(java.util.Collection<?> elementsToRetain)
MultisetNote: This method ignores how often any element might appear in
c, and only cares whether or not an element appears at all.
If you wish to remove one occurrence in this multiset for every occurrence
in c, see Multisets.retainOccurrences(Multiset, Multiset).
This method refines Collection.retainAll(java.util.Collection<?>) to further specify that
it may not throw an exception in response to any of elements
being null or of the wrong type.
retainAll in interface java.util.Collection<E>retainAll in interface Multiset<E>retainAll in class java.util.AbstractCollection<E>Multisets.retainOccurrences(Multiset, Multiset)public void clear()
clear in interface java.util.Collection<E>clear in class java.util.AbstractCollection<E>public java.util.Set<Multiset.Entry<E>> entrySet()
MultisetMultiset.Entry instances, each providing an element of the multiset and
the count of that element. This set contains exactly one entry for each
distinct element in the multiset (thus it always has the same size as the
Multiset.elementSet()). The order of the elements in the element set is
unspecified.
The entry set is backed by the same data as the multiset, so any change
to either is immediately reflected in the other. However, multiset changes
may or may not be reflected in any Entry instances already
retrieved from the entry set (this is implementation-dependent).
Furthermore, implementations are not required to support modifications to
the entry set at all, and the Entry instances themselves don't
even have methods for modification. See the specific implementation class
for more details on how its entry set handles modifications.
public boolean equals(@Nullable
java.lang.Object object)
true if the given object is also a multiset and contains equal
elements with equal counts, regardless of order.
This implementation returns true if object is a multiset
of the same size and if, for each element, the two multisets have the same
count.
public int hashCode()
((element == null) ? 0 : element.hashCode()) ^ count(element)
over all distinct elements in the multiset. It follows that a multiset and
its entry set always have the same hash code.
This implementation returns the hash code of Multiset.entrySet().
public java.lang.String toString()
It is recommended, though not mandatory, that this method return the
result of invoking Multiset.toString() on the Multiset.entrySet(), yielding a
result such as [a x 3, c, d x 2, e].
This implementation returns the result of invoking toString on
Multiset.entrySet().