Key Terms in This Chapter

This section explains key technical terms used in this chapter, with an emphasis on clarifying how these terms are used in the Java ES context.

application component

A custom-developed software component that performs a specific computing function, providing business services to end users or to other application components. An application component usually conforms to a distributed component model (such as CORBA and the J2EE platform). These components, singly or combined, can be encapsulated as web services.

architecture

A design that shows the logical and physical building blocks of a distributed application (or some other software system) and their relationships to one another. In the case of a distributed enterprise application, the architectural design generally includes both the application’s logical architecture and deployment architecture.

business service

An application component or component assembly that performs business logic on behalf of multiple clients (and is therefore a multithreaded process). A business service can also be an assembly of distributed components encapsulated as a web service or a stand-alone server.

client

Software that requests software services. A client can be a service that requests another service or a GUI component accessed by an end user.

deployment architecture

A high-level design that depicts the mapping of a logical architecture to a physical computing environment. The physical environment includes the computers in an intranet or Internet environment, the network links between them, and any other physical devices needed to support the software.

logical architecture

A design that depicts the logical building blocks of a distributed application and the relationships (or interfaces) between these building blocks. The logical architecture includes both the distributed application components and the infrastructure services components needed to support them.

server

A multithreaded software process (as distinguished from a hardware server) that provides a distributed service or cohesive set of services for clients that access the service by way of an external interface.

web service

A service that conforms to standardized Internet protocols for accessibility, service encapsulation, and discovery. The standards include the SOAP messaging protocol, the WSDL (Web Services Description Language) interface definition, and the UDDI (Universal Description, Discovery and Integration) registry standard.