Adds an item to the tail of this Ringbuffer. Overflow policy determines
what will happen if there is no space left in this ringbuffer.
If OVERWRITE
was passed, the new item will overwrite the oldest one
regardless of the configured time-to-live.
In the case when FAIL
was specified the add operation will keep failing
until the oldest item in this Ringbuffer will reach its time-to-live.
The returned value is the sequence number of the added item. You can read the added item using this number.
the item to add
overflow policy to be used
the sequence of the added item or -1
if the insert did not succeed
Adds all items in the specified array to the tail of this Ringbuffer.
The behavior of this method is essentially the same as the one of
the add
method.
The method does not guarantee that the inserted items will have contiguous sequence numbers.
items to be added
overflow policy to be used
the sequence number of the last written item from the specified array
capacity of this Ringbuffer
Destroys this object cluster-wide. Clears all resources taken for this object.
Returns the unique name of this object.
Returns the key of the partition that this DistributedObject is assigned to.
For a partitioned data structure, the returned value will not be null
,
but otherwise undefined
.
Returns the service name for this object.
Returns the head sequence. The head is the side of the ringbuffer where the oldest items are found.
If the ringbuffer is empty, the head will be one more than the tail.
The initial value of the head is 0
.
head sequence of this Ringbuffer
Reads a batch of items from the Ringbuffer. If the number of available
items starting at sequence
is smaller than maxCount
, then this
method will not wait for more items to arrive. Instead, available
items will be returned.
If there are fewer items available than minCount
, then this call will
not return a response until a necessary number of items becomes available.
If startSequence
is smaller than the smallest sequence still available
in the Ringbuffer headSequence
, then the smallest available
sequence will be used as the start sequence, and the minimum/maximum
number of items will be attempted to be read from there on.
If startSequence
is bigger than the last available sequence in the
Ringbuffer tailSequence
, then the last available sequence
plus one will be used as the start sequence, and the call will block
until further items become available, and it can read at least the
minimum number of items.
filter
argument is provided to select only the items that are needed
to be read. If the filter is not provided, all items will be read.
Otherwise, only the items where the filter function returns true are returned.
Using filters is a good way to prevent getting items that are of no value
to the receiver. This reduces the amount of IO and the number of operations being executed,
and can result in a significant performance improvement. Note that,
filtering logic must be defined on the server-side.
sequence number of the first item to be read.
minimum number of items to be read.
maximum number of items to be read.
optional filter to be applied to the items
Reads a single item from this Ringbuffer.
If the sequence is equal to the current tail sequence plus one, this call will not return a response until an item is added. If it is more than that, an error will be thrown.
Unlike queue's take
, this method does not remove an item from the
Ringbuffer. This means that the same item can be read by multiple
processes.
the sequence number of the item to read
the item that was read
Returns the remaining capacity of this ringbuffer.
The returned value could be stale as soon as it is returned.
If the time-to-live was NOT set in the configuration, the remaining capacity will always be equal to the capacity.
remaining capacity of this Ringbuffer
Returns the number of the items in this Ringbuffer.
If time-to-live was not configured for this ringbuffer, the size will always be equal to the capacity after the first loop is completed around the ring. This is because no items are getting removed and are overwritten instead.
size of this Ringbuffer
Returns the tail sequence. The tail is the side of the Ringbuffer at which the items are added.
The initial value of the tail sequence is -1
.
tail sequence of this Ringbuffer
Generated using TypeDoc
A Ringbuffer is a data structure where the content is stored in a ring-like structure. A ringbuffer has a fixed capacity, so it won't grow beyond that capacity and endanger the stability of the system. If that capacity is exceeded, the oldest item in the ringbuffer is overwritten.
Methods that require serialization/deserialization may throw RangeError, e.g when there is no suitable serializer for a certain type.