Framework

Framework implements J2EE-based OLTP, batch, and foundation architecture as technical environment of J2EE development. it provides a development environment where application developers focus on the business process development.The framework components are split into 2 sections, the architectural mechanisms and the integration mechanisms. Architectural Mechanisms are framework infrastructure components. Integration mechanism are components which can be used for integrating systems

1) Channel Tier

This tier provides various protocol services for communication with Presentation. Converts different message formats to internal standard formats, check validity, and supports posting to hosts that provides actual business services. Features of the channel tier are as below:• Handles multiple request protocols • Comprehensive connectivity to a large variety of systems• Uses Asynchronous IO for TCP/IP • Configurable audit logging with pre and post formatted inputs and outputs• Plug-in support for validations• Re-use validations across transactions• Push data to a client via TCP/IP for long running transactions.

2) Biz Tier

Biz tier comprises of Service Orchestrator, Service Provider and Data abstraction components. Message router in channel tier forward the message to Service orchestrator.

a. Service Orchestrator

This sub component deals with invocation of appropriate service provider for the transaction being sent by message router. It comprises of message listener, transaction coordinator, service command, and process orchestrator.Message Listener is implemented as a message driven bean and provides mechanism for receiving transaction from message router in channel tier. Process orchestrator manages the invocation of one or more than one service commands to execute transaction. Services are invoked synchronously. Process orchestrator caches the work flow information from the repository.Service command converts XML message to the DTO java object as required by service provider which executes the transaction. Service command then invokes service provider using the DTO java object. Following figure shows the flow of transaction within Service orchestrator.

b. Service Provider

This component comprises of process component, EIS wrapper, referential component or domain component. Service provider manages the business processes for the transaction. Service provider communicates with the back end systems that provides the business functionality. Data required by host system is provided by service provider by formatting or generating data from the available data with transaction. Data is retrieved from database using referential component. EIS wrapper acts as a proxy for allowing back end services to be invoked by service provider.

c. System Integration Mechanisms

Component in the service provider communicate with multiple host system via system interface. System interface allows for a standard mechanism for clients to connect to host systems. The system interface consists of a basic interface which is used by clients to communicate with different back-end systems. An interface to a specific back-end system can be obtained via a System interface factory. The system interface factory will create an instance of the appropriate back-end system connector and return the interface for the same. The system interface handles this posting of the reversal, which is completely independent of any application developer intervention. In case the reversal transaction so posted fails, then the transaction is marked as pending reversal in a local log. The log is a database table. When a user initiates another transaction, the reversal transaction is attempted again. This auto reversal function assumes that the host system will return a success for a reversal transaction for which the original transaction does not exist. The auto reversal function will not handle any failures for the reversals sent.

3) J2EE Fundamental Facility

Fundamental facility provides sets of architectural services and architectural classes that can be used for building an application or framework.