private static class Synchronized.SynchronizedMultiset<E> extends Synchronized.SynchronizedCollection<E> implements Multiset<E>
Multiset.Entry<E>
Modifier and Type | Field and Description |
---|---|
(package private) java.util.Set<E> |
elementSet |
(package private) java.util.Set<Multiset.Entry<E>> |
entrySet |
private static long |
serialVersionUID |
delegate, mutex
Constructor and Description |
---|
SynchronizedMultiset(Multiset<E> delegate,
java.lang.Object mutex) |
Modifier and Type | Method and Description |
---|---|
int |
add(E e,
int n)
Adds a number of occurrences of an element to this multiset.
|
int |
count(java.lang.Object o)
Returns the number of occurrences of an element in this multiset (the count of the
element).
|
(package private) Multiset<E> |
delegate() |
java.util.Set<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 o)
Compares the specified object with this multiset for equality.
|
int |
hashCode()
Returns the hash code for this multiset.
|
int |
remove(java.lang.Object o,
int n)
Removes a number of occurrences of the specified element from this multiset.
|
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. |
add, addAll, clear, contains, containsAll, forEach, isEmpty, iterator, parallelStream, remove, removeAll, removeIf, retainAll, size, spliterator, stream, toArray, toArray
toString
clone, finalize, getClass, notify, notifyAll, wait, wait, wait
add, contains, containsAll, forEach, forEachEntry, iterator, remove, removeAll, retainAll, size, spliterator, toString
@CheckForNull transient java.util.Set<E> elementSet
@CheckForNull transient java.util.Set<Multiset.Entry<E>> entrySet
private static final long serialVersionUID
Multiset<E> delegate()
delegate
in class Synchronized.SynchronizedCollection<E>
public int count(@CheckForNull java.lang.Object o)
Multiset
Object.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(E e, int n)
Multiset
occurrences ==
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>
e
- the element to add occurrences of; may be null only if explicitly allowed by the
implementationn
- the number of occurrences of the element to add. May be zero, in which case
no change will be made.public int remove(@CheckForNull java.lang.Object o, int n)
Multiset
occurrences == 1
, this is functionally equivalent to the call remove(element)
.public int setCount(E element, int count)
Multiset
setCount
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(E element, int oldCount, int newCount)
Multiset
Multiset.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 java.util.Set<E> elementSet()
Multiset
If 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>
public java.util.Set<Multiset.Entry<E>> entrySet()
Multiset
Multiset.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(@CheckForNull java.lang.Object o)
Multiset
true
if the
given object is also a multiset and contains equal elements with equal counts, regardless of
order.public int hashCode()
Multiset
((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.