de.otto.synapse.messagestore

Class InMemoryRingBufferMessageStore

java.lang.Object

de.otto.synapse.messagestore.InMemoryRingBufferMessageStore

All Implemented Interfaces:

MessageStore, WritableMessageStore, java.lang.AutoCloseable

@ThreadSafe
public class InMemoryRingBufferMessageStore
extends java.lang.Object
implements WritableMessageStore

Thread-safe in-memory implementation of a circular MessageStore that is storing all messages in insertion order with a configurable capacity.

Each time an element is added to a full message store, the message store automatically removes its head element.

Constructor Summary

Constructors

Constructor and Description
InMemoryRingBufferMessageStore() Creates a new instance with default capacity of 100.
InMemoryRingBufferMessageStore(int capacity) Creates a new instance with specified capacity.

Method Summary

Modifier and Type	Method and Description
void	add(Message<java.lang.String> message) Adds a Message to the MessageStore.
ChannelPosition	getLatestChannelPosition() Returns the latest ChannelPosition of the MessageStore.
int	size() Returns the number of messages contained in the MessageStore.
java.util.stream.Stream<Message<java.lang.String>>	stream() Returns a Stream of messages contained in the MessageStore.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface de.otto.synapse.messagestore.MessageStore

close

Constructor Detail

InMemoryRingBufferMessageStore

public InMemoryRingBufferMessageStore()

Creates a new instance with default capacity of 100.

InMemoryRingBufferMessageStore

public InMemoryRingBufferMessageStore(int capacity)

Creates a new instance with specified capacity.

Parameters:

capacity - the size of the underlying ring buffer.

Method Detail

add

public void add(Message<java.lang.String> message)

Adds a Message to the MessageStore.

If the capacity of the ring buffer is reached, the oldest message is removed

Specified by:

add in interface WritableMessageStore

Parameters:

message - the message to add

getLatestChannelPosition

public ChannelPosition getLatestChannelPosition()

Returns the latest ChannelPosition of the MessageStore.

The position is calculated by merging the optional positions of the messages.

Messages without positions will not change the latest ChannelPosition. If no message contains position information, the returned ChannelPosition is ChannelPosition.fromHorizon()

Specified by:

getLatestChannelPosition in interface MessageStore

Returns:

ChannelPosition

stream

public java.util.stream.Stream<Message<java.lang.String>> stream()

Returns a Stream of messages contained in the MessageStore.

The stream will maintain the insertion order of the messages.

Specified by:

stream in interface MessageStore

Returns:

Stream of messages

size

public int size()

Description copied from interface: MessageStore

Returns the number of messages contained in the MessageStore.

Primarily used for testing purposes. If the MessageStore can not implement this without major performance impacts (like, for example, having to download and parse huge files from S3), the method is not required to be implemented.

Specified by:

size in interface MessageStore

Returns:

number of messages