Introduction to Application Integration

This document provides instructions for using adapters via application views in a WebLogic Integration environment. Adapters may be purchased or developed using the BEA WebLogic Integration Adapter Development Kit (ADK). This document explains how to define application view services and events and use them in your business processes in a WebLogic Integration environment.

Familiarizing Yourself with Basic Concepts

If you are not familiar with the basic concepts of application integration, we recommend that you take the time to read the overview of application integration provided in Introducing Application Integration. Then you will be ready to learn how to address practical issues, such as when to use one application integration method rather than another, and how to implement the method you select.

Creating an Interface to an Adapter

For each adapter to be used in the enterprise, provide an interface to the services and events that it provides. You can create such an interface in either of two ways: by defining application views or by writing custom code.

Application views provide the most convenient method of accessing an adapter's resources. In most situations you will probably choose this method for exposing the application functions provided by each adapter. However, if you require more control over an adapter's functions than that afforded by application views, you may also write custom code.

You are responsible for deciding whether your enterprise can derive greater benefit from application views or custom code. The following sections provide basic guidelines for choosing between these two methods. For details, see Defining an Application View, and Using Application Views by Writing Custom Code.

When to Define an Application View

Most enterprise information system (EIS) applications can be integrated easily by defining application views. In general, you should define application views if one or more of the following criteria are true:

You have more than one EIS in your enterprise, and you lack developers with detailed, thorough knowledge of all systems.
You want to construct business processes using WebLogic Workshop.
You need to be able to update the parameters of an adapter or one of its processes.

When to Write Custom Code

You should write custom code as an interface to an adapter only if one or more of the following criteria are true:

You have only one EIS in your enterprise and your developer has thorough, detailed knowledge of the EIS involved in the business processes being coded.
You do not need to use the business process management (BPM) functions implemented as business processes using WebLogic Workshop.
Your code will never require changes.

Defining an Application View

An application view for an adapter is an XML-based interface between WebLogic Server and a particular EIS application. You must define an application view for each adapter used by your enterprise.

What Is Defined by an Application View Definition

When you define an application view, you must configure communication parameters for it, and then add services and/or events to it. The application view's services and events expose specific functions of the application. The communication parameters of the application view govern how the application view connects to the target EIS.

Where application view information is to be stored
A unique name for the application view
Parameters for the following:

Application
Network connections between the application and the application view
Management of the pool of connections available to the application view
Load balancing to be performed by the application view

How to Define an Application View

This section provides a high-level overview of the procedure you must complete to define application views for adapters. For detailed instructions, see Defining an Application View.

Step 1: Deploy Adapters

Adapters are available within the Integration folder of BEA_HOME folder when the BEA products are installed. For more information about deploying adapters, see Step 1: Deploy Adapters

Step 2: Log On to the Application Integration Design Console

The Application Integration Design Console displays all the application views in your WebLogic Integration environment, organized in folders. You must log in to view the console. For details about logging on to the Application Integration Design Console, see Step 2: Log On to the Application Integration Design Console.

Step 3: Define the Application Context for an Application View

Application view files are stored in a file system related to a WebLogic Workshop project. The first step in defining an application view for an adapter is to define the application context; you can either specify an existing project or define a new file repository for application view information.

Step 4: Add Folders

Folders are provided to help you organize and manage application views. Create or select an existing folder in which the application view will reside. For details about adding a folder, see Step 4: Add a Folder.

Step 5: Define Application View

Create a new application view for the appropriate adapter. An application view enables business processes to make use of the specified adapter's target EIS. For detailed information, see Step 5: Define an Application View.

Step 6: Create New or Select Existing Connection

Choose the type of connection factory to associate with the application view. You can select a connection factory within an existing instance of the adapter or create a connection factory within new adapter instance.

Step 7: Add Services and Events to the Application View

Services and events support a subset of an application's business processes by enabling WebLogic Server clients to interact with the application functions you specify. The services and events offered by an application view allow specific types of transactions between WebLogic Server and the EIS application.

For details about adding services and events to an application view, see the following topics:

Step 8: Perform Final Configuration

Perform final configuration tasks that will allow you to test services and events. For details about performing final configuration tasks, see Step 8: Perform Final Configuration Tasks.

Step 9: Test Services and Events

Step 10: Publish Application View

Using an Application View in a Business Process

Once you define an application view in your WebLogic Integration environment, you can deploy it on WebLogic Server and use it to implement your enterprise's business processes.

You can use application views in business processes in either of the following ways:

By designing business processes in WebLogic Workshop
By writing custom code

When an application view is used in your business process, the end result is a deployed electronic representation of your enterprise's business process. The business process uses the Application View control to execute transactional interactions with the backend EIS system to accomplish specific business tasks.

Using an Application View in WebLogic Workshop

The most common way to use an application view in your enterprise's business is by designing a business process in WebLogic Workshop. A graphical user interface (GUI) is used for designing business processes. These business processes can include application view services and events accessed through the Application View control and the Message Broker Subscription control.

Choosing a Method for Implementing a Business Process

WebLogic Integration allows you to implement your business processes by using either of two methods: by creating a business process in WebLogic Workshop or by writing custom code. Any business operation can be implemented as a business process.

Custom coding, however, should be attempted only if the target business process is extremely simple and specialized. In this document, custom coding is described only as an alternate method to be used in situations that require it.

When to Use WebLogic Workshop to Create a Business Process

Use WebLogic Workshop to implement a business process if one or more of the following criteria are true:

Your business processes require complicated error management, persistent processes, and sophisticated conditional branching.

For example, if your business process must receive numerous events, select a subset of them, perform complex branched actions, generate many complex messages, and send the messages to various WebLogic Server clients, then you should use WebLogic Workshop.

Your business process requires periodic changes.

WebLogic Workshop reduces the number of required compile/test/debug cycles.

Your developers (like those in most organizations) are valuable and scarce.
Your organization can afford to allocate developers for the job of implementing business processes in code.

Using an Application View Control in Business Processes

A business process developer can use an Application View control to provide users of BEA WebLogic Workshop with the means to interact with an EIS application. The interaction is implemented using a Java API. A business process developer is not required to be an expert on the EIS to use its capabilities. A developer can invoke application view services both synchronously and asynchronously, and can subscribe to application view events using simple Java objects. For more information about using Application View controls, see the Building Integration Applications topic in the WebLogic Workshop Help at the following URL:

Using the Application Integration Design Console