Java EE Patterns (edit)

• Numbers on the arrows indicate a possible call sequence in a request.
• patterns
• Front Controller: initial point of contact for handling all related requests. The Front Controller centralizes control logic that might otherwise be duplicated, and manages the key request handling activities.
• Transfer Object: carries multiple data elements across a tier
• Transfer Object Assembler:  builds an application model as a composite Transfer Object. The Transfer Object Assembler aggregates multiple Transfer Objects from various business components and services, and returns it to the client. 
• Persistent Domain Object: Rich domain object, ie. having rich behavior/bus.logic and persistent 
• Web Service Broker: exposes and brokers one or more services using XML and web protocols.
• The Web Service Broker can be generalised to a Protocol Broker.
• Service Facade: encapsulates business-tier components and exposes a coarse-grained service to remote clients. Clients access a Service Façade instead of accessing business components directly. 
• The place of the Service Facade can also be taken by a (domain) Gateway.
• Service: Fine-grained, reusable logic in an EJB with local access only, product of decomposition
• Data Access Object: abstracts and encapsulates all access to the persistent store. The Data Access Object manages the connection with the data source to obtain and store data. 
• Asynchronous Resource Integrator: Invocation of a Service from a Message-Driven Bean (invoked by a messaging system via JMS)
• Payload extractor: factor out the (reusable) type checking and error handling for a MDB message into a reusable interceptor; poison messages moved by the interceptor to a “dead letter queue” via a stateless EJB using the JMS API
• Resource Binder: put a custom resource into JNDI using a @Singleton with @Startup and the JNDI API (Context.(re)bind()).