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.

adoption scenario

An overall reason for deploying Java ES software that describes the software system you start with and the goal you are trying to achieve. Four basic Java ES adoption scenarios exist: new system, replacement, extension, and upgrade.

component

A unit of software logic from which distributed applications are built. A component can be one of the system components included in Java ES or an application component that is custom developed. An application component usually conforms to a distributed component model (such as CORBA or the J2EE^TM platform) and performs a specific computing function. These components, singly or combined, provide business services and can be encapsulated as web services.

distributed enterprise application

An application with logic that spans a network or Internet environment (the distributed aspect) and with a scope and scale that meet the needs of a production environment or service provider (the enterprise aspect).

end user

A person who uses a distributed application often through a graphical user interface such as an Internet browser or mobile device GUI. The number of concurrent end users supported by an application is an important determinant of the deployment architecture of the application.

service

A software function performed for one or more clients. This function might be at a very low level such as a memory management service or at a high level such as a credit check business service. A high-level service can consist of a family of individual services. Services can be local (available to local clients) or distributed (available to remote clients).

product component

Java ES system service components, which provide the main Java ES infrastructure services, and Java ES service quality components, which enhance those system services. Product components are selectable within the Java ES installer.

service quality component

A type of system component included in Java ES. These components enhance the availability, security, scalability, serviceability, and other qualities of system service components and distributed application components.

shared component

A type of system component included in Java ES. Shared components, usually libraries, provide local services to other system components.

system component

Any software package or set of packages included in Java ES and installed by the Java ES installer. Several kinds of system components exist: product components that provide Java ES infrastructure services, and shared components that provide local services to other system components.

system service

One or more distributed services that define the unique functionality provided by Java ES. System services normally require the support of a number of service quality components, a number of shared components, or some of both.

system service component

A type of system component included in Java ES. System services components provide the main Java ES infrastructure services: portal services, identity and security services, web and application services, and availability services.