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, isEmpty, iterator, remove, removeAll, retainAll, size, toArray, toArray
toString
clone, finalize, getClass, notify, notifyAll, wait, wait, wait
add, contains, containsAll, iterator, remove, removeAll, retainAll, toString
transient java.util.Set<E> elementSet
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(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(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(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.