52 Part II Message Endpoints
Message endpoints represent where any EAI solution will succeed or fail technically. The func-
tions and data of an organization’s applications, databases, files, and services are exposed
through message endpoints.
Message endpoints are the components of an EAI system that interface with applica-
tions, databases, and other data sources and destinations, and they serve as the gateways to
the sending and receiving applications attached to your system. For example, if you want to
send a message each time a certain table in a database is updated, you would use a mes-
sage endpoint to detect the change, create the message, and then send the message.
Message endpoints generally fall into one of four categories. We will explore each of
these categories in this part of the book.
■ Database endpoints This type of endpoint connects directly to a
database. In the EAI arena, you often will need to communicate directly
to a database layer of an application or a stand-alone database. You
can accomplish this through a database endpoint. Database endpoints
are typically aware of the tables, stored procedures, and triggers with
which they interact.
■ Application endpoints These endpoints communicate with the
business tier of an application. They typically respond to events occur-
ring inside the application. Application endpoints and calls from the
presentation tier are subject to the same logic.
■ File endpoints These endpoints communicate directly with files on
the file system. Often, EAI solutions must integrate data from external
sources arriving, for example, as flat files via FTP. A file endpoint is
responsible for taking the flat file and converting it into meaningful
messages. Also, the file endpoint is often used to send data to organi-
zations or systems that cannot accept information in real time.
■ Web endpoints These endpoints communicate directly with Web
services or Web pages. For example, when the source of your data is
an external Web site, the Web endpoint handles this type of work.