Interface Summary
MessageGroup A group of messages that are correlated with each other and should be processed in the same context.
MessageGroupStore Interface for storage operations on groups of messages linked by a group id.
MessageStore Strategy interface for storing and retrieving messages.
MetadataStore Strategy interface for storing metadata from certain adapters to avoid duplicate delivery of messages, for example.

Class Summary
MessageGroupQueue A BlockingQueue that is backed by a MessageGroupStore.
MessageGroupStoreReaper Convenient configurable component to allow explicit timed expiry of MessageGroup instances in a MessageGroupStore.
PropertiesPersistingMetadataStore Properties file-based implementation of MetadataStore.
SimpleMessageGroup Represents a mutable group of correlated messages that is bound to a certain MessageStore and group id.
SimpleMessageStore Map-based implementation of MessageStore and MessageGroupStore.
SimpleMetadataStore Simple implementation of MetadataStore that uses an in-memory map only.