Package io.atomix.client.set

Interface AsyncDistributedMultiset<E>

All Superinterfaces:
AsyncDistributedCollection<E>, AsyncIterable<E>, AsyncPrimitive, DistributedPrimitive
public interface AsyncDistributedMultiset<E> extends AsyncDistributedCollection<E>
Asynchronous distributed multiset.

  • Method Details

    • count

      CompletableFuture<Integer> count(Object element)
      Returns the number of occurrences of an element in this multiset (the count of the element). Note that for an 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.

      Parameters:
      element - the element to count occurrences of
      Returns:
      the number of occurrences of the element in this multiset; possibly zero but never negative

    • add

      CompletableFuture<Integer> add(E element, int occurrences)
      Adds a number of occurrences of an element to this multiset. Note that if occurrences == 1, this method has the identical effect to AsyncDistributedCollection.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.
      Parameters:
      element - the element to add occurrences of; may be null only if explicitly allowed by the implementation
      occurrences - the number of occurrences of the element to add. May be zero, in which case no change will be made.
      Returns:
      the count of the element before the operation; possibly zero
      Throws:
      IllegalArgumentException - if occurrences is negative, or if this operation would result in more than Integer.MAX_VALUE occurrences of the element
      NullPointerException - if element is null and this implementation does not permit null elements. Note that if occurrences is zero, the implementation may opt to return normally.

    • remove

      CompletableFuture<Integer> remove(Object element, int occurrences)
      Removes a number of occurrences of the specified element from this multiset. If the multiset contains fewer than this number of occurrences to begin with, all occurrences will be removed. Note that if occurrences == 1, this is functionally equivalent to the call remove(element).
      Parameters:
      element - the element to conditionally remove occurrences of
      occurrences - the number of occurrences of the element to remove. May be zero, in which case no change will be made.
      Returns:
      the count of the element before the operation; possibly zero
      Throws:
      IllegalArgumentException - if occurrences is negative

    • setCount

      CompletableFuture<Integer> setCount(E element, int count)
      Adds or removes the necessary occurrences of an element such that the element attains the desired count.
      Parameters:
      element - the element to add or remove occurrences of; may be null only if explicitly allowed by the implementation
      count - the desired count of the element in this multiset
      Returns:
      the count of the element before the operation; possibly zero
      Throws:
      IllegalArgumentException - if count is negative
      NullPointerException - if element is null and this implementation does not permit null elements. Note that if count is zero, the implementor may optionally return zero instead.

    • setCount

      CompletableFuture<Boolean> setCount(E element, int oldCount, int newCount)
      Conditionally sets the count of an element to a new value, as described in setCount(Object, int), provided that the element has the expected current count. If the current count is not oldCount, no change is made.
      Parameters:
      element - the element to conditionally set the count of; may be null only if explicitly allowed by the implementation
      oldCount - the expected present count of the element in this multiset
      newCount - the desired count of the element in this multiset
      Returns:
      true if the condition for modification was met. This implies that the multiset was indeed modified, unless oldCount == newCount.
      Throws:
      IllegalArgumentException - if oldCount or newCount is negative
      NullPointerException - if element is null and the implementation does not permit null elements. Note that if oldCount and newCount are both zero, the implementor may optionally return true instead.

    • elementSet

      AsyncDistributedSet<E> elementSet()
      Returns the set of distinct elements contained in this multiset. The element set is backed by the same data as the multiset, so any change to either is immediately reflected in the other. The order of the elements in the element set is unspecified.

      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().

      Returns:
      a view of the set of distinct elements in this multiset

    • entrySet

      AsyncDistributedSet<com.google.common.collect.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. This set contains exactly one entry for each distinct element in the multiset (thus it always has the same size as the 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.

      Returns:
      a set of entries representing the data of this multiset

    • sync

      default DistributedMultiset<E> sync()
      Description copied from interface: AsyncPrimitive
      Returns a synchronous wrapper around the asynchronous primitive.
      Specified by:
      sync in interface AsyncDistributedCollection<E>
      Specified by:
      sync in interface AsyncPrimitive
      Returns:
      the synchronous primitive

    • sync

      DistributedMultiset<E> sync(Duration operationTimeout)
      Description copied from interface: AsyncPrimitive
      Returns a synchronous wrapper around the asynchronous primitive.
      Specified by:
      sync in interface AsyncDistributedCollection<E>
      Specified by:
      sync in interface AsyncPrimitive
      Parameters:
      operationTimeout - the synchronous operation timeout
      Returns:
      the synchronous primitive