The Java EE 5 Tutorial

Common Client Interface

This section describes how components use the Connector architecture Common Client Interface (CCI) API and a resource adapter to access data from an EIS.

Defined by the J2EE Connector architecture specification, the CCI defines a set of interfaces and classes whose methods allow a client to perform typical data access operations. The CCI interfaces and classes are as follows:

• ConnectionFactory: Provides an application component with a Connection instance to an EIS.

• Connection: Represents the connection to the underlying EIS.

• ConnectionSpec: Provides a means for an application component to pass connection-request-specific properties to the ConnectionFactory when making a connection request.

• Interaction: Provides a means for an application component to execute EIS functions, such as database stored procedures.

• InteractionSpec: Holds properties pertaining to an application component’s interaction with an EIS.

• Record: The superclass for the various kinds of record instances. Record instances can be MappedRecord, IndexedRecord, or ResultSet instances, all of which inherit from the Record interface.

• RecordFactory: Provides an application component with a Record instance.

• IndexedRecord: Represents an ordered collection of Record instances based on the java.util.List interface.

A client or application component that uses the CCI to interact with an underlying EIS does so in a prescribed manner. The component must establish a connection to the EIS’s resource manager, and it does so using the ConnectionFactory. The Connection object represents the actual connection to the EIS and is used for subsequent interactions with the EIS.

The component performs its interactions with the EIS, such as accessing data from a specific table, using an Interaction object. The application component defines the Interaction object using an InteractionSpec object. When the application component reads data from the EIS (such as from database tables) or writes to those tables, it does so using a particular type of Record instance: either a MappedRecord, an IndexedRecord, or a ResultSet instance. Just as the ConnectionFactory creates Connection instances, a RecordFactory creates Record instances.

Note, too, that a client application that relies on a CCI resource adapter is very much like any other Java EE client that uses enterprise bean methods.