Sun Java Enterprise System Glossary


EAR file

(enterprise archive file) (n.) An archive file that contains a J2EE application. EAR files have the .ear extension.


(Electronic Business XML) (adj.) A group of specifications designed to enable enterprises to conduct business through the exchange of XML-based messages. It is sponsored by OASIS and the United Nations Centre for the Facilitation of Procedures and Practices in Administration, Commerce and Transport (U.N./CEFACT).

ebXML registry

(Electronic Business XML registry) (n.) A federated registry and repository that manages all types of electronic content described by standard and extensible metadata.


(elliptic curve cryptography) (n.) A public-key cryptography for mobile or wireless environments that operates on elliptic curves.


(electronic commerce) (n.) A term for business conducted over the Internet.

EHLO command

(n.) An SMTP command that queries a server to find out if the server supports extended SMTP commands. Defined in RFC 1869.


(enterprise information system) (n.) The applications that constitute an enterprise's existing system for handling company-wide information. These applications provide an information infrastructure for an enterprise. An enterprise information system offers a well-defined set of services to its clients. These services are exposed to clients as local or remote interfaces or both. Examples of enterprise information systems include enterprise resource planning systems, mainframe transaction processing systems, and legacy database systems. Specific examples include R/3, PeopleSoft, Tuxedo, and CICS.

EIS resource

(n.) A resource that provides enterprise information system-specific functionality to its clients. Examples are a record or set of records in a database system, a business object in an enterprise resource planning system, and a transaction program in a transaction processing system.

EJB container

(n.) A container that implements the EJB component contract of the J2EE architecture. This contract specifies a runtime environment for an enterprise bean that includes security, concurrency, life-cycle management, transactions, deployment, naming, and other services. An EJB container is provided by an EJB or J2EE server. See also container.

EJB container provider

(n.) A vendor that supplies an EJB container.

EJB context

(n.) An object that allows an enterprise bean to invoke services provided by the container and to obtain the information about the caller of a client-invoked method.

EJB home object

(n.) An object that provides the life-cycle operations (create, remove, find) for an enterprise bean. The class for the EJB home object is generated by the container's deployment tools. The EJB home object implements the enterprise bean's home interface. The client references an EJB home object to perform life-cycle operations on an EJB object. The client uses a JNDI name to locate an EJB home object.

EJB JAR file

(n.) An archive file that contains an EJB module. EJB JAR files have the .jar extension.

EJB module

(n.) A deployable unit that consists of one or more enterprise beans and an EJB deployment descriptor. See also module.

EJB object

(n.) An object whose class implements the enterprise bean's remote interface. A client never references an enterprise bean instance directly; a client always references an EJB object. The class of an EJB object is generated by a container's deployment tools.

EJB server

(n.) Software that provides services to an EJB container. For example, an EJB container typically relies on a transaction manager that is part of the EJB server to perform the two-phase commit across all the participating resource managers. The J2EE architecture assumes that an EJB container is hosted by an EJB server from the same vendor, so it does not specify the contract between these two entities. An EJB server can host one or more EJB containers.

EJB server provider

(n.) A vendor that supplies an EJB server.


(EJB Query Language) (n.) Defines the queries for the finder and select methods of an entity bean having container-managed persistence. A subset of SQL92, EJB QL has extensions that allow navigation over the relationships defined in an entity bean's abstract schema.

EJB technology

(Enterprise JavaBeansTM technology) (n.) A component architecture for the development and deployment of object-oriented, distributed, enterprise-level applications. Applications written using the Enterprise JavaBeans architecture are scalable, transactional, and secure. See also enterprise bean.

ejbc utility

(n.) The compiler for enterprise beans. This utility checks all EJB classes and interfaces for compliance with the EJB specification and generates stubs and skeletons.


(n.) A member of a larger set, for example, a data unit within an array or a logic element. In an XML file, an element is the basic structural unit, delimited by tags. An XML element contains subelements or data and might contain attributes.

elliptic curve cryptography

See ECC.

empty tag

(n.) An XML tag that does not enclose any content.


(n.) Process of protecting information from unauthorized use by making the information unintelligible. Some encryption methods employ codes, called keys, which are used to encrypt the information. See also decryption.


(1) (n.) The IP address or host name of a machine in a load-balanced cluster.

(2) (n.) In the Java Message Service, a message consumer. See message-driven bean.

(3) (n.) A Java class, typically a servlet or stateless session bean, annotated with the javax.jws.WebService annotation. This annotation defines the class as a web service endpoint, which receives messages from web service clients.

end user

(n.) 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.


See event notification service.

enterprise bean

(n.) A J2EE component that implements a business task or business entity and is hosted by an EJB container; either an entity bean, message-driven bean, or session bean. See also container.

enterprise bean provider

(n.) An application developer who produces enterprise bean classes, remote and home interfaces, and deployment descriptor files, and packages them in an EJB JAR file.

enterprise network

(n.) A network that consists of collections of networks connected to each other over a geographically dispersed area. The enterprise network serves the needs of a widely distributed company and is used by the company’s mission-critical applications.


(1) (n.) In XML files, a distinct, individual item that can be included in an XML document by referencing it. Such an entity reference can name an entity as small as a character (for example, &lt;, which references the less-than symbol or left angle bracket, <). An entity reference can also reference an entire document, an external entity, or a collection of DTD definitions.

entity bean

(n.) An EJB 1.x or 2.x enterprise bean that represents persistent data maintained in a database. An entity bean can manage its own persistence or can delegate this function to its container. An entity bean is identified by a primary key. If the container in which an entity bean is hosted crashes, the entity bean, its primary key, and any remote references survive the crash. Entity beans are always transactional and multiuser aware. See also persistence, message-driven bean, read-only bean, and session bean.

entity reference

(n.) A reference to an entity that is substituted for the reference when the XML document is parsed. It can reference a predefined entity such as &lt; or reference one that is defined in the DTD. In the XML data, the reference could be to an entity that is defined in the local subset of the DTD or to an external XML file (an external entity). The DTD can also carve out a segment of DTD specifications and give it a name so that it can be reused (included) at multiple points in the DTD by defining a parameter entity.


(n.) A measure of the randomness in a closed system. Specifically in the context of SSL, multiple seeds are used in order to introduce entropy (ensure randomness) in random number generation.


(n.) A group of attributes and a unique distinguished name.

entry distribution

(n.) Method of distributing directory entries across more than one server in order to scale to support large numbers of entries.

entry ID list

(n.) A list of entry IDs. Each index that the directory uses is composed of a table of index keys and matching entry ID lists. The entry ID list is used by the directory to build a list of candidate entries that might match the client application's search request.


(n.) The phase of a robot's operation in which the robot seeks resources, including extracting and following hypertext links.


(n.) A container for transport information about the sender and the recipient of an email message. This information is not part of the message header. Envelopes are used by various email programs as messages are moved from place to place. Users see only the header and body of a message.

envelope field

(n.) A named item of information, such as RCPT TO, in a message envelope.

equality index

(n.) An index which allows you to search efficiently for entries containing a specific attribute value.


(enterprise resource planning) (n.) A multi-module software system that typically includes a relationship database and applications for managing purchasing, inventory, personnel, customer service, shipping, financial planning, and other important aspects of the business.

error handler

(n.) A program that handles errors. In Messaging Server, the error handler issues error messages and processes error-handler action forms after the postmaster fills them out.

error handler action form

(n.) A form sent to the postmaster account that accompanies a received message that Messaging Server cannot handle. The postmaster fills out the form to instruct the server how to process the message.


See extended simple mail transfer protocol.


(n.) enterprise service provider.

ETRN command

(n.) An SMTP command enabling a client to request that the server start the processing of its mail queues for messages that are waiting at the server for the client machine. Defined in RFC 1985.


(1) (n.) An entry with an associated date and time in a calendar. For example, an event might be a new meeting or appointment on a calendar.

(2) (n.) A named action that triggers a response from a module or external Java Naming and Directory Interface TM (JNDI) resource.

(3) (n.) A change in the state, mastery, severity, or description of a managed object.

(4) (n.) In the Application Server, an occurrence that triggers the action associated with a server self-management rule. See also management rule.

event notification service

(n.) A generic service that accepts reports of server-level events that can be categorized and then notifies other servers that have registered interest in certain categories of events. Allows the Java Naming and Directory InterfaceTM (JNDI) Service to act as a bridge to a remote JNDI server.


(n.) Part of an electronic mail delivery system that allows a message to be delivered to a list of addressees. Mail expanders are used to implement mail lists. Users send messages to a single address (for example, and the mail expander takes care of delivery to the mailboxes in the list. Also called mail exploders. See also EXPN command.


(n.) The act of converting a message addressed to a mail list into enough copies for each mail list member. Applies to the MTA processing of mail lists.

expires header

(n.) The expiration time of the returned document specified by the remote server.

EXPN command

(n.) An SMTP command for expanding a mail list. Defined in RFC 821.

expunge a message

(v.) To permanently remove a message that has been deleted from the INBOX. See also delete a message, purge a message.

extended simple mail transfer protocol

(n.) An Internet message transport protocol. ESMTP adds optional commands to the SMTP command set for enhanced functionality, including the ability for ESMTP servers to discover which commands are implemented by the remote site.

extensible markup language

See XML.

extensible style language

See XSL.

extensible style language transformation


external entity

(n.) An entity that exists as an external XML file, which is included in the XML document using an entity reference.

external subset

(n.) That part of a DTD that is defined by references to external DTD files.


(n.) The process of locating hypertext links in a document. Each extracted link is added to the URL pool for further processing.


(n.) An extension of a company’s intranet onto the Internet to allow customers, suppliers, and remote workers access to the data.