Software - Articles  Streaming Architecture  This short article
describes a J2EE architectural pattern known as a Streaming
Architecture. For a comprehensive practical example with full
source code, as well as a performance comparison with other
architectures, see Streaming Presidents.   Improve application
server scalability by streaming response data through the
application server, thereby never holding more than a small
portion of a result set in memory at once.   Consider a J2EE-
based system that includes reporting functionality that may,
depending on the selection criteria, return several hundred rows
of data in response to a single request.  Sun's J2EE Blueprints
traditionally structure applications with a (1) web-tier, within
which a Front Controller servlet runs, and (2) an application
tier wherein session beans encapsulating core business logic
run. The front controller invokes a handler that, in turn,
remotely invokes the appropriate session bean to perform its
business logic. The session bean retur