Glossary

This glossary provides definitions for common terms used to describe the Sun ONE Application Server deployment and development environment. For a glossary of standard J2EE terms, please see the J2EE glossary at:

   http://java.sun.com/j2ee/glossary.html

access control. The means of securing your Sun ONE Application Server by controlling who and what has access to it.

ACL. Access Control List. ACLs are text files that contain lists identifying who can access the resources stored on your Sun ONE Application Server. See also general ACL.

activation. The process of transferring an enterprise bean's state from secondary storage to memory.

Administration interface. The set of browser based forms used to configure and administer the Sun ONE Application Server. See also CLI.

administration server. An application server instance dedicated to providing the administrative functions of the Sun ONE Application Server, including deployment, browser-based administration, and access from the command-line interface (CLI) and Integrated Development Environment (IDE).

administrative domain. Multiple administrative domains is a feature within the Sun ONE Application Server that allows different administrative users to create and manage their own domains. A domain is a set of instances, created using a common set of installed binaries in a single system.

API. Applications Program Interface. A set of instructions that a computer program can use to communicate with other software or hardware that is designed to interpret that API.

applet. A small application written in Java that runs in a web browser. Typically, applets are called by or embedded in web pages to provide special functionality. By contrast, a servlet is a small application that runs on a server.

application. A group of components packaged into an .ear file with a J2EE application deployment descriptor. See also component, module.

application client container. See container.

application server. A reliable, secure, and scalable software platform in which business applications are run. Application servers typically provide high-level services to applications, such as component lifecycle, location, and distribution and transactional resource access,

application tier. A conceptual division of a J2EE application:

client tier: The user interface (UI). End users interact with client software (such as a web browser) to use the application.

server tier: The business logic and presentation logic that make up your application, defined in the application's components.

data tier: The data access logic that enables your application to interact with a data source.

assembly. The process of combining discrete components of an application into a single unit that can be deployed. See also deployment.

asynchronous communication. A mode of communication in which the sender of a message need not wait for the sending method to return before it continues with other work.

attribute. A name-value pair in a request object that can be set by a servlet. Also a name-value pair that modifies an element in an XML file. Contrast with parameter. More generally, an attribute is a unit of metadata.

auditing. The method(s) by which significant events are recorded for subsequent examination, typically in error or security breach situations.

authentication. The process by which an entity (such as a user) proves to another entity (such as an application) that it is acting on behalf of a specific identity (the user's security identity). Sun ONE Application Server supports basic, form-based, and SSL mutual authentication. See also client authentication, digest authentication, host-IP authentication, pluggable authentication.

authorization. The process by which access to a method or resource is determined. Authorization in the J2EE platform depends upon whether the user associated with a request through authentication is in a given security role. For example, a human resources application may authorize managers to view personal employee information for all employees, but allow employees to only view their own personal information.

backup store. A repository for data, typically a file system or database. A backup store can be monitored by a background thread (or sweeper thread) to remove unwanted entries.

bean-managed persistence. Data transfer between an entity bean's variables and a data store. The data access logic is typically provided by a developer using Java Database Connectivity (JDBC) or other data access technologies. See also container-managed persistence.

bean-managed transaction. Where transaction demarcation for an enterprise bean is controlled programmatically by the developer. See also container-managed transaction.

BLOB. Binary Large OBject. A data type used to store and retrieve complex object fields. BLOBs are binary or serializable objects, such as pictures, that translate into large byte arrays, which are then serialized into container-managed persistence fields.

BMP. See bean-managed persistence.

BMT. See bean-managed transaction.

broker. The Sun ONE Message Queue entity that manages JMS message routing, delivery, persistence, security, and logging, and which provides an interface that allows an administrator to monitor and tune performance and resource use.

business logic. The code that implements the essential business rules of an application, rather than data integration or presentation logic.

CA. See certificate authority or connector architecture.

cached rowset. A CachedRowSet object permits you to retrieve data from a data source, then detach from the data source while you examine and modify the data. A cached row set keeps track both of the original data retrieved, and any changes made to the data by your application. If the application attempts to update the original data source, the row set is reconnected to the data source, and only those rows that have changed are merged back into the database.

Cache Control Directives. Cache-control directives are a way for Sun ONE Application Server to control what information is cached by a proxy server. Using cache-control directives, you override the default caching of the proxy to protect sensitive information from being cached, and perhaps retrieved later. For these directives to work, the proxy server must comply with HTTP 1.1.

callable statement. A class that encapsulates a database procedure or function call for databases that support returning result sets from stored procedures.

certificate. Digital data that specifies the name of an individual, company, or other entity, and certifies that the public key included in the certificate belongs to that entity. Both clients and servers can have certificates.

certificate authority. A company that sells certificates over the Internet, or a department responsible for issuing certificates for a company's intranet or extranet.

cipher. A cryptographic algorithm (a mathematical function), used for encryption or decryption.

CKL. Compromised Key List. A list, published by a certificate authority, that indicates any certificates that either client users or server users should no longer trust. In this case, the key has been compromised. See also CRL.

classloader. A Java component responsible for loading Java classes according to specific rules. See also classpath.

classpath. A path that identifies directories and JAR files where Java classes are stored. See also classloader.

CLI. Command-line interface. An interface that enables you to type executable instructions at a user prompt. See also Administration interface.

client authentication. The process of authenticating client certificates by cryptographically verifying the certificate signature and the certificate chain leading to the CA on the trust CA list. See also authentication, certificate authority.

client contract. A contract that determines the communication rules between a client and the EJB container, establishes a uniform development model for applications that use enterprise beans, and guarantees greater reuse of beans by standardizing the relationship with the client.

CMP. See container-managed persistence.

CMR. See container-managed relationship.

CMT. See container-managed transaction.

co-locate. To position a component in the same memory space as a related component in order avoid remote procedure calls and improve performance.

column. A field in a database table.

commit. To complete a transaction by sending the required commands to the database. See rollback, transaction.

component. A web application, enterprise bean, message-driven bean, application client, or connector. See also application, module.

component contract. A contract that establishes the relationship between an enterprise bean and its container.

configuration. The process of tuning the server or providing metadata for a component. Normally, the configuration for a specific component is kept in the component's deployment descriptor file. See also administration server, deployment descriptor.

connection factory. An object that produces connection objects that enable a J2EE component to access a resource. Used to create JMS connections (TopicConnection or QueueConnection) which allow application code to make use of the provided JMS implementation. Application code uses the JNDI Service to locate connection factory objects using a JNDI Name.

Connection Pool. allows highly efficient access to a database by caching and reusing physical connections, thus avoiding connection overhead and allowing a small number of connections to be shared between a large number of threads. See also JDBC connection pool

connector. A standard extension mechanism for containers to provide connectivity to EISs. A connector is specific to an EIS and consists of a resource adapter and application development tools for EIS connectivity. The resource adapter is plugged in to a container through its support for system level contracts defined in the connector architecture.

connector architecture.

An architecture for the integration of J2EE applications with EISs. There are two parts to this architecture: a EIS vendor-provided resource adapter and a J2EE server that allows this resource adapter to plug in. This architecture defines a set of contracts that a resource adapter has to support to plug in to a J2EE server, for example, transactions, security and resource management.

container. An entity that provides life cycle management, security, deployment, and runtime services to a specific type of J2EE component. Sun ONE Application Server provides web and EJB containers, and supports application client containers. See also component.

container-managed persistence. Where the EJB container is responsible for entity bean persistence. Data transfer between an entity bean's variables and a data store, where the data access logic is provided by the Sun ONE Application Server. See also bean-managed persistence.

container-managed relationship. A relationship between fields in a pair of classes where operations on one side of the relationship affect the other side.

container-managed transaction. Where transaction demarcation for an enterprise bean is specified declaratively and automatically controlled by the EJB container See also bean-managed transaction.

control descriptor. A set of enterprise bean configuration entries that enable you to specify optional individual property overrides for bean methods, plus enterprise bean transaction and security properties.

conversational state. Where the state of an object changes as the result of repeated interactions with the same client. See also persistent state.

cookie. A small collection of information that can be transmitted to a calling web browser, then retrieved on each subsequent call from that browser so the server can recognize calls from the same client. Cookies are domain-specific and can take advantage of the same web server security features as other data interchange between your application and the server.

CORBA. Common Object Request Broker Architecture. A standard architecture definition for object-oriented distributed computing.

COSNaming Service. An an IIOP-based naming service.

CosNaming provider. To support a global JNDI name space (accessible to IIOP application clients), Sun ONE Application Server includes J2EE based CosNaming provider which supports binding of CORBA references (remote EJB references).

create method. A method for customizing an enterprise bean at creation.

CRL. Certificate Revocation List. A list, published by a certificate authority, that indicates any certificates that either client users or server users should no longer trust. In this case, the certificate has been revoked. See also CKL.

data access logic. Business logic that involves interacting with a data source.

database. A generic term for Relational Database Management System (RDBMS). A software package that enables the creation and manipulation of large amounts of related, organized data.

database connection. A database connection is a communication link with a database or other data source. Components can create and manipulate several database connections simultaneously to access data.

data source. A handle to a source of data, such as a database. Data sources are registered with the iPlanet Application Server and then retrieved programmatically in order to establish connections and interact with the data source. A data source definition specifies how to connect to the source of data.

DataSource Object. A DataSource object has a set of properties that identify and describe the real world data source that it represents.

declarative security. Declaring security properties in the component's configuration file and allowing the component's container (for instance, a bean's container or a servlet engine) to manage security implicitly. This type of security requires no programmatic control. Opposite of programmatic security. See container-managed persistence.

declarative transaction. See container-managed transaction.

decryption. The process of transforming encrypted information so that it is intelligible again.

delegation. An object-oriented technique for using the composition of objects as an implementation strategy. One object, which is responsible for the result of an operation, delegates the implementation to another object, its delegatee. For example, a classloader often delegates the loading of some classes to its parent.

deployment. The process of distributing the files required by an application to an application server to make the application available to run on the application server. See also assembly.

deployment descriptor. An XML file provided with each module and application that describes how they should be deployed. The deployment descriptor directs a deployment tool to deploy a module or application with specific container options and describes specific configuration requirements that a deployer must resolve.

destination resource. An objects that represents Topic or Queue destinations. Used by applications to read/write to Queues or publish/subscribe to Topics. Application code uses the JNDI Service to locate JMS resource objects using a JNDI Name.

digest authentication. A for of authentication that allows the user to authenticate based on user name and password without sending the user name and password as cleartext.

digital signature. an electronic security mechanism used to authenticate both a message and the signer.

directory server. See Sun ONE Directory Server.

Distinguished Name. See DN, DN attribute.

distributable session. A user session that is distributable among all servers in a cluster.

distributed transaction. A single transaction that can apply to multiple heterogeneous databases that may reside on separate servers.

Document Root. The document root (sometimes called the primary document directory) is the central directory that contains all the virtual server's files you want to make available to remote clients.

Domain Registry. The Domain Registry is a single data structure that contains domain-specific information, for all the domains created and configured on an installation of Sun ONE Application Server, such as domain name, domain location, domain port, domain host.

DTD. Document Type Definition. A description of the structure and properties of a class of XML files.

DN. Distinguished Name. The string representation for the name of an entry in a directory server.

DN attribute. Distinguished Name attribute. A text string that contains identifying information for an associated user, group, or object.

dynamic redeployment. The process of redeploying a component without restarting the server.

dynamic reloading. The process of updating and reloading a component without restarting the server. By default, servlet, JavaServer Page (JSP), and enterprise bean components can be dynamically reloaded. Also known as versioning.

EAR file. Enterprise ARchive file. An archive file that contains a J2EE application. EAR files have the .ear extension. See also JAR file.

e-commerce. Electronic commerce. A term for business conducted over the Internet.

EIS. Enterprise Information System. This can be interpreted as a packaged enterprise application, a transaction system, or a user application. Often referred to as an EIS. Examples of EISs include: R/3, PeopleSoft, Tuxedo, and CICS.

EJB container. See container.

EJB QL. EJB Query Language. A query language that provides for navigation across a network of entity beans defined by container-managed relationships.

EJB technology. An enterprise bean is a server-side component that encapsulates the business logic of an application. The business logic is the code that fulfills the purpose of the application. In an inventory control application, for example, the enterprise beans might implement the business logic in methods called checkInventoryLevel and orderProduct. By invoking these methods, remote clients can access the inventory services provided by the application. See also container, entity bean, message-driven bean, and session bean.

ejbc utility. The compiler for enterprise beans. It checks all EJB classes and interfaces for compliance with the EJB specification, and generates stubs and skeletons.

element. A member of a larger set; for example, a data unit within an array, or a logic element. In an XML file, it is the basic structural unit. An XML element contains subelements or data, and may contain attributes.

encapsulate. To localize knowledge within a module. Because objects encapsulate data and implementation, the user of an object can view the object as a black box that provides services. Instance variables and methods can be added, deleted, or changed, but if the services provided by the object remain the same, code that uses the object can continue to use it without being rewritten.

encryption. The process of transforming information so it is unintelligible to anyone but the intended recipient.

entity bean. An enterprise bean that relates to physical data, such as a row in a database. Entity beans are long lived, because they are tied to persistent data. Entity beans are always transactional and multi-user aware. See message-driven bean, read-only bean, session bean.

ERP. Enterprise Resource Planning. A multi-module software system that supports enterprise resource planning. An ERP system typically includes a relational database and applications for managing purchasing, inventory, personnel, customer service, shipping, financial planning, and other important aspects of the business.

event. A named action that triggers a response from a module or application.

external JDNI resource. Allows the JNDI Service to act as a bridge to a remote JNDI server.

facade. Where an application-specific stateful session bean is used to manage various Enterprise JavaBeans (EJBs).

factory class. A class that creates persistence managers. See also connection factory.

failover. A recovery process where a bean can transparently survive a server crash.

finder method. Method which enables clients to look up a bean or a collection of beans in a globally available directory.

firewall. an electronic boundary that allows a network administrator to restrict the flow of information across networks in order to enforce security.

File Cache. The file cache contains information about files and static file content. The file cache is turned on by default.

form action handler. A specially defined method in servlet or application logic that performs an action based on a named button on a form.

FQDN. Fully Qualified Domain Name. The full name of a system, containing its hostname and its domain name.

general ACL. A named list in the Sun ONE Directory Server that relates a user or group with one or more permissions. This list can be defined and accessed arbitrarily to record any set of permissions.

generic servlet. A servlet that extends javax.servlet.GenericServlet. Generic servlets are protocol-independent, meaning that they contain no inherent support for HTTP or any other transport protocol. Contrast with HTTP servlet.

global database connection. A database connection available to multiple components. Requires a resource manager.

global transaction. A transaction that is managed and coordinated by a transaction manager and can span multiple databases and processes. The transaction manager typically uses the XA protocol to interact with the database backends. See local transaction.

granularity level. The approach to dividing an application into pieces. A high level of granularity means that the application is divided into many smaller, more narrowly defined Enterprise JavaBeans (EJBs). A low level of granularity means the application is divided into fewer pieces, producing a larger program.

group. A group of users that are related in some way. Group membership is usually maintained by a local system administrator. See user, role.

handle. An object that identifies an enterprise bean. A client may serialize the handle, and then later deserialize it to obtain a reference to the bean.

Heuristic Decision. The transactional mode used by a particular transaction. A transaction has to either Commit or Rollback.

home interface. A mechanism that defines the methods that enable a client to create and remove an enterprise bean.

host-IP authentication. A security mechanism used for of limiting access to the Administration Server, or the files and directories on a web site by making them available only to clients using specific computers.

HTML. Hypertext Markup Language. A coding markup language used to create documents that can be displayed by web browsers. Each block of text is surrounded by codes that indicate the nature of the text.

HTML page. A page coded in HTML and intended for display in a web browser.

HTTP. Hypertext Transfer Protocol. The Internet protocol that fetches hypertext objects from remote hosts. It is based on TCP/IP.

HTTP servlet. A servlet that extends javax.servlet.HttpServlet. These servlets have built-in support for the HTTP protocol. Contrast with generic servlet.

HTTPS. HyperText Transmission Protocol, Secure. HTTP for secure transactions.

IDE. Integrated Development Environment. Software that allows you to create, assemble, deploy, and debug code from a single, easy-to-use interface.

IIOP. Internet Inter-ORB Protocol. Transport-level protocol used by both Remote Method Invocation (RMI) over IIOP and Common Object Request Broker Architecture (CORBA).

IIOP Listener. The IIOP listener is a listen socket that listens on a specified port and accepts incoming connections from CORBA based client application

IP address. A structured, numeric identifier for a computer or other device on a TCP/IP network. The format of an IP address is a 32-bit numeric address written as four numbers separated by periods. Each number can be zero to 255. For example, 123.231.32.2 could be an IP address.

IMAP. Internet Message Access Protocol.

isolation level. See transaction isolation level.

J2EE. Java 2 Enterprise Edition. An environment for developing and deploying multi-tiered, web-based enterprise applications. The J2EE platform consists of a set of services, application programming interfaces (APIs), and protocols that provide the functionality for developing these applications.

JAF. The JavaBeans Activation Framework (JAF) integrates support for MIME data types into the Java platform. See Mime Types.

JAR file. Java ARchive file. A file used for aggregating many files into one file. JAR files have the.jar extension.

JAR file contract. Java ARchive contract that specifies what information must be in the enterprise bean package.

JAR file format. Java ARchive file format. A platform-independent file format that aggregates many files into one file. Multiple applets and their requisite components (class files, images, sounds, and other resource files) can be bundled in a JAR file and subsequently downloaded to a browser in a single HTTP transaction. The JAR files format also supports file compression and digital signatures.

JavaBean. A portable, platform-independent reusable component model.

Java IDL. Java Interface Definition Language. APIs written in the Java programming language that provide a standards-based compatibility and connectivity with Common Object Request Broker Architecture (CORBA).

JavaMail session. An object used by an application to interact with a mail store. Application code uses the JNDI Service to locate JavaMail session resources objects using a JNDI name.

JAXM. Java API for XML Messaging. Enables applications to send and receive document-oriented XML messages using the SOAP standard. These messages can be with or without attachments.

JAXP. Java API for XML Processing. A Java API that supports processing of XML documents using DOM, SAX, and XSLT. Enables applications to parse and transform XML documents independent of a particular XML processing implementation.

JAXR. Java API for XML Registry. Provides a uniform and standard Java API for accessing different kinds of XML registries. Enables users to build, deploy and discover web services.

JAX-RPC. Java API for XML-based Remote Procedure Calls. Enables developers to build interoperable web applications and web services based on XML-based RPC protocols.

JDBC. Java Database Connectivity. A standards-based set of classes and interfaces that enable developers to create data-aware components. JDBC implements methods for connecting to and interacting with data sources in a platform- and vendor-independent way.

JDBC connection pool. A pool that combines the JDBC data source properties used to specify a connection to a database with the connection pool properties.

JDBC resource. A resource used to connect an application running within the application server to a database using an existing JDBC connection pool. Consists of a JNDI name (which is used by the application) and the name of an existing JDBC connection pool.

JDK. Java Development Kit. The software that includes the APIs and tools that developers need to build applications for those versions of the Java platform that preceded the Java 2 Platform. See also JDK.

JMS. Java Message Service. A standard set of interfaces and semantics that define how a JMS client accesses the facilities of a JMS message service. These interfaces provide a standard way for Java programs to create, send, receive, and read messages.

JMS-administered object. A pre-configured JMS object—a connection factory or a destination—created by an administrator for use by one or more JMS clients.

The use of administered objects allows JMS clients to be provider-independent; that is, it isolates them from the proprietary aspects of a provider. These objects are placed in a JNDI name space by an administrator and are accessed by JMS clients using JNDI lookups.

JMS client. An application (or software component) that interacts with other JMS clients using a JMS message service to exchange messages.

JMS connection factory. The JMS administered object a JMS client uses to create a connection to a JMS message service.

JMS destination. The physical destination in a JMS message service to which produced messages are delivered for routing and subsequent delivery to consumers. This physical destination is identified and encapsulated by an JMS administered object that a JMS client uses to specify the destination for which it is producing messages and/or from which it is consuming messages.

JMS messages. Asynchronous requests, reports, or events that are consumed by JMS clients. A message has a header (to which additional fields can be added) and a body. The message header specifies standard fields and optional properties. The message body contains the data that is being transmitted.

JMS provider. A product that implements the JMS interfaces for a messaging system and adds the administrative and control functions needed for a complete product.

JMS Service. Software that provides delivery services for a JMS messaging system, including connections to JMS clients, message routing and delivery, persistence, security, and logging. The message service maintains physical destinations to which JMS clients send messages, and from which the messages are delivered to consuming clients.

JNDI. Java Naming and Directory Interface. This is a standard extension to the Java platform, providing Java technology-enabled applications with a unified interface to multiple naming and directory services in the enterprise. As part of the Java Enterprise API set, JNDI enables seamless connectivity to heterogeneous enterprise naming and directory services.

JNDI name. A name used to access a resource that has been registered in the JNDI naming service.

JRE. Java Runtime Environment. A subset of the Java Development Kit (JDK) consisting of the Java virtual machine, the Java core classes, and supporting files that provides runtime support for applications written in the Java programming language. See also JDK.

JSP. JavaServer Page. A text page written using a combination of HTML or XML tags, JSP tags, and Java code. JSPs combine the layout capabilities of a standard browser page with the power of a programming language.

jspc utility. The compiler for JSPs. It checks all JSPs for compliance with the JSP specification.

JTA. Java Transaction API. An API that allows applications and J2EE servers to access transactions.

JTS. Java Transaction Service. The Java service for processing transactions.

key-pair file. See trust database.

LDAP. Lightweight Directory Access Protocol. LDAP is an open directory access protocol that runs over TCP/IP. It is scalable to a global size and millions of entries. Using Sun ONE Directory Server, a provided LDAP server, you can store all of your enterprise's information in a single, centralized repository of directory information that any application server can access through the network.

LDIF. LDAP Data Interchange Format. Format used to represent Sun ONE Directory Server entries in text form.

lifecycle event. A stage in the server life cycle, such as startup or shutdown.

lifecycle module. A module that listens for and performs its tasks in response to events in the server life cycle.

Listener. A class, registered with a posting object, that says what to do when an event occurs.

local database connection. The transaction context in a local connection is local to the current process and to the current data source, not distributed across processes or across data sources.

local interface. An interface that provides a mechanism for a client that is located in the same Java Virtual Machine (JVM) with a session or entity bean to access that bean.

local session. A user session that is only visible to one server.

local transaction. A transaction that is native to one database and is restricted within a single process. Local transactions work only against a single backend. Local transactions are typically demarcated using JDBC APIs. See also global transaction.

mapping. The ability to tie an object-oriented model to a relational model of data, usually the schema of a relational database. The process of converting a schema to a different structure. Also refers to the mapping of users to security roles.

MDB. See message-driven bean.

message-driven bean. An enterprise bean that is an asynchronous message consumer. A message-driven bean has no state for a specific client, but its instance variables may contain state across the handling of client messages, including an open database connection and an object reference to an EJB object. A client accesses a message-driven bean by sending messages to the destination for which the message-driven bean is a message listener.

messaging. A system of asynchronous requests, reports, or events used by enterprise applications that allows loosely coupled applications to transfer information reliably and securely.

metadata. Information about a component, such as its name, and specifications for its behavior.

MIME Data Type. MIME (Multi-purpose Internet Mail Extension) types control what types of multimedia files your system supports.

module. A web application, enterprise bean, message-driven bean, application client, or connector that has been deployed individually, outside an application. See also application, component, lifecycle module.

NTV. Name, Type, Value.

object persistence. See persistence.

O/R mapping tool. Object-to-relational [database] tool. A mapping tool within the Sun ONE Application Server Administrative interface that creates XML deployment descriptors for entity beans.

package. A collection of related classes that are stored in a common directory. They are often literally packaged together in a Java archive JAR file. See also assembly, deployment.

parameter. A name/value pair sent from the client, including form field data, HTTP header information, and so on, and encapsulated in a request object. Contrast with attribute. More generally, an argument to a Java method or database- prepared command.

passivation. A method of releasing a bean's resources from memory without destroying the bean. In this way, a bean is made to be persistent, and can be recalled without the overhead of instantiation.

permission. A set of privileges granted or denied to a user or group. See also ACL.

persistence. For enterprise beans, the protocol for transferring the state of an entity bean between its instance variables and an underlying database. Opposite of transience. For sessions, the session storage mechanism.

persistence manager. The entity responsible for the persistence of the entity beans installed in the container.

persistent state. Where the state of an object is kept in persistent storage, usually a database.

pluggable authentication.

A mechanism that allows J2EE applications to use the Java Authentication and Authorization Service (JAAS) feature from the J2SE platform. Developers can plug in their own authentication mechanisms.

point-to-point delivery model. Producers address messages to specific queues; consumers extract messages from queues established to hold their messages. A message is delivered to only one message consumer.

pooling. The process of providing a number of preconfigured resources to improve performance. If a resource is pooled, a component can use an existing instance from the pool rather than instantiating a new one. In the Sun ONE Application Server, database connections, servlet instances, and enterprise bean instances can all be pooled.

POP3. Post Office Protocol

prepared command. A database command (in SQL) that is precompiled to make repeated execution more efficient. Prepared commands can contain parameters. A prepared statement contains one or more prepared commands.

prepared statement. A class that encapsulates a QUERY, UPDATE, or INSERT statement that is used repeatedly to fetch data. A prepared statement contains one or more prepared commands.

presentation layout. The format of web page content.

presentation logic. Activities that create a page in an application, including processing a request, generating content in response, and formatting the page for the client. Usually handled by a web application.

primary key. The unique identifier that enables the client to locate a particular entity bean.

primary key class name. A variable that specifies the fully qualified class name of a bean's primary key. Used for JNDI lookups.

principal. The identity assigned to an entity as a result of authentication.

private key. See public key cryptography.

process. Execution sequence of an active program. A process is made up of one or more threads.

programmatic security. The process of controlling security explicitly in code rather than allowing the component's container (for instance, a bean's container or a servlet engine) to handle it. Opposite of declarative security.

programmer-demarcated transaction. See bean-managed transaction.

property. A single attribute that defines the behavior of an application component. In the server.xml file, a property is an element that contains a name/value pair.

public key cryptography. A form of cryptography in which each user has a public key and a private key. Messages are sent encrypted with the receiver's public key; the receiver decrypts them using the private key. Using this method, the private key never has to be revealed to anyone other than the user.

publish/subscribe delivery model. Publishers and subscribers are generally anonymous and may dynamically publish or subscribe to a topic. The system distributes messages arriving from a topic's multiple publishers to its multiple subscribers.

queue. An object created by an administrator to implement the point-to-point delivery model. A queue is always available to hold messages even when the client that consumes its messages is inactive. A queue is used as an intermediary holding place between producers and consumers.

QOS. QOS (Quality of Service) refers to the performance limits you set for a server instance or virtual server. For example, if you are an ISP, you might want to charge different amounts of money for virtual servers depending on how much bandwidth is provided. You can limit two areas: the amount of bandwidth and the number of connections.

RAR file. Resource ARchive. A JAR archive that contains a resource adapter.

RDB. Relational database.

RDBMS. Relational database management system.

read-only bean. An entity bean that is never modified by an EJB client. See also entity bean.

realm. A scope over which a common security policy is defined and enforced by the security administrator of the security service. Also called a security policy domain or security domain in the J2EE specification.

remote interface. One of two interfaces for an Enterprise JavaBean. The remote interface defines the business methods callable by a client.

request object. An object that contains page and session data produced by a client, passed as an input parameter to a servlet or JavaServer Page (JSP).

resource manager. An object that acts as a facilitator between a resource such as a database or message broker, and client(s) of the resource such as Sun ONE Application Server processes. Controls globally-available data sources.

resource reference. An element in a deployment descriptor that identifies the component's coded name for the resource.

response object. An object that references the calling client and provides methods for generating output for the client.

ResultSet. An object that implements the java.sql.ResultSet interface. ResultSets are used to encapsulate a set of rows retrieved from a database or other source of tabular data.

reusable component. A component created so that it can be used in more than one capacity, for instance, by more than one resource or application.

RMI. Remote Method Invocation. A Java standard set of APIs that enable developers to write remote interfaces that can pass objects to remote processes.

RMIC. Remote Method Invocation Compiler.

role. A functional grouping of subjects in an application, represented by one or more groups in a deployed environment. See also user, group.

rollback. Cancellation of a transaction.

row. A single data record that contains values for each column in a table.

RowSet. An object that encapsulates a set of rows retrieved from a database or other source of tabular data. RowSet extends the java.sql.ResultSet interface, enabling ResultSet to act as a JavaBeans component.

RPC. Remote Procedure Call. A mechanism for accessing a remote object or service.

runtime system. The software environment in which programs run. The runtime system includes all the code necessary to load programs written in the Java programming language, dynamically link native methods, manage memory, and handle exceptions. An implementation of the Java virtual machine is included, which may be a Java interpreter.

SAF. Server Application Function. A function that participates in request processing and other server activities

schema. The structure of the underlying database, including the names of tables, the names and types of columns, index information, and relationship (primary and foreign key) information.

Secure Socket Layer. See SSL.

security. A screening mechanism that ensures that application resources are only accessed by authorized clients.

serializable object. An object that can be deconstructed and reconstructed, which enables it to be stored or distributed among multiple servers.

server instance. A Sun ONE Application Server can contain multiple instances in the same installation on the same machine. Each instance has its own directory structure, configuration, and deployed applications. Each instance can also contain multiple virtual servers. See also virtual server.

servlet. An instance of the Servlet class. A servlet is a reusable application that runs on a server. In the Sun ONE Application Server, a servlet acts as the central dispatcher for each interaction in an application by performing presentation logic, invoking business logic, and invoking or performing presentation layout.

servlet engine. An internal object that handles all servlet metafunctions. Collectively, a set of processes that provide services for a servlet, including instantiation and execution.

servlet runner. The part of the servlet engine that invokes a servlet with a request object and a response object. See servlet engine.

session. An object used by a servlet to track a user's interaction with a web application across multiple HTTP requests.

session bean. An enterprise bean that is created by a client; usually exists only for the duration of a single client-server session. A session bean performs operations for the client, such as calculations or accessing other EJBs. While a session bean may be transactional, it is not recoverable if a system crash occurs. Session bean objects can be either stateless (not associated with a particular client) or stateful (associated with a particular client), that is, they can maintain conversational state across methods and transactions. See also stateful session bean, stateless session bean.

session cookie. A cookie that is returned to the client containing a user session identifier. See also sticky cookie.

session timeout. A specified duration after which the Sun ONE Application Server can invalidate a user session. See session.

single sign-on. A situation where a user's authentication state can be shared across multiple J2EE applications in a single virtual server instance.

SMTP. Simple Mail Transport Protocol

SNMP. SNMP (Simple Network Management Protocol) is a protocol used to exchange data about network activity. With SNMP, data travels between a managed device and a network management station (NMS). A managed device is anything that runs SNMP: hosts, routers, your web server, and other servers on your network. The NMS is a machine used to remotely manage that network.

SOAP. The Simple Object Access Protocol (SOAP) uses a combination of XML-based data structuring and Hyper Text Transfer Protocol (HTTP) to define a standardized way of invoking methods in objects distributed in diverse operating environments across the Internet.

SQL. Structured Query Language. A language commonly used in relational database applications. SQL2 and SQL3 designate versions of the language.

SSL. Secure Sockets Layer. A protocol designed to provide secure communications on the Internet.

state. 1. The circumstances or condition of an entity at any given time. 2. A distributed data storage mechanism which you can use to store the state of an application using the Sun ONE Application Server feature interface IState2. See also conversational state, persistent state.

stateful session bean. A session bean that represents a session with a particular client and which automatically maintains state across multiple client-invoked methods.

stateless session bean. A session bean that represents a stateless service. A stateless session bean is completely transient and encapsulates a temporary piece of business logic needed by a specific client for a limited time span.

sticky cookie. A cookie that is returned to the client to force it to always connect to the same server process. See also session cookie.

stored procedure. A block of statements written in SQL and stored in a database. You can use stored procedures to perform any type of database operation, such as modifying, inserting, or deleting records. The use of stored procedures improves database performance by reducing the amount of information that is sent over a network.

streaming. A technique for managing how data is communicated through HTTP. When results are streamed, the first portion of the data is available for use immediately. When results are not streamed, the whole result must be received before any part of it can be used. Streaming provides a way to allow large amounts of data to be returned in a more efficient way, improving the perceived performance of the application.

system administrator. The person who administers Sun ONE Application Server software and deploys Sun ONE Application Server applications.

Sun ONE Application Server RowSet. A RowSet object that incorporates the Sun ONE Application Server extensions.

Sun ONE Directory Server. The Sun ONE version of Lightweight Directory Access Protocol (LDAP). Every instance of Sun ONE Application Server uses Sun ONE Directory Server to store shared server information, including information about users and groups. See also LDAP.

Sun ONE Message Queue. The Sun ONE enterprise messaging system that implements the Java Message Service (JMS) open standard: it is a JMS provider.

TLS. Transport Layer Security. A protocol that provides encryption and certification at the transport layer, so that data can flow through a secure channel without requiring significant changes to the client and server applications.

table. A named group of related data in rows and columns in a database.

thread. An execution sequence inside a process. A process may allow many simultaneous threads, in which case it is multi-threaded. If a process executes each thread sequentially, it is single-threaded.

topic. An object created by an administrator to implement the publish/subscribe delivery model. A topic may be viewed as node in a content hierarchy that is responsible for gathering and distributing messages addressed to it. By using a topic as an intermediary, message publishers are kept separate from message subscribers.

transaction context. A transaction's scope, either local or global. See local transaction, global transaction.

transaction isolation level. Determines the extent to which concurrent transactions on a database are visible to one-another.

transaction manager. An object that controls a global transaction, normally using the XA protocol. See global transaction.

transaction. A set of database commands that succeed or fail as a group. All the commands involved must succeed for the entire transaction to succeed.

Transaction Recovery. Automatic or manual recovery of distributed transactions.

Transaction Attribute. A transaction attribute controls the scope of a transaction.

transience. A protocol that releases a resource when it is not being used. Opposite of persistence.

trust database. I security file that contains the public and private keys; also referred to as the key-pair file.

URI. Universal Resource Identifier. Describes a specific resource at a domain. Locally described as a subset of a base directory, so that /ham/burger is the base directory and a URI specifies toppings/cheese.html. A corresponding URL would be http://domain:port/toppings/cheese.html.

URL. Uniform Resource Locator. An address that uniquely identifies an HTML page or other resource. A web browser uses URLs to specify which pages to display. A URL describes a transport protocol (for example, HTTP, FTP), a domain (for example, www.my-domain.com), and optionally a URI.

user. A person who uses an application. Programmatically, a user consists of a user name, password, and set of attributes that enables an application to recognize a client. See also group, role.

user session. A series of user application interactions that are tracked by the server. Sessions maintain user state, persistent objects, and identity authentication.

versioning. See dynamic reloading.

virtual server. A virtual web server that serves content targeted for a specific URL. Multiple virtual servers may serve content using the same or different host names, port numbers, or IP addresses. The HTTP service can direct incoming web requests to different virtual servers based on the URL. Also called a virtual host.

A web application can be assigned to a specific virtual server. A server instance can have multiple virtual servers. See also server instance.

WAR file. Web ARchive. A Java archive that contains a web module. WAR files have the.war extension.

web application. A collection of servlets, JavaServer Pages, HTML documents, and other web resources, which might include image files, compressed archives, and other data. A web application may be packaged into an archive (a WAR file) or exist in an open directory structure.

Sun ONE Application Server also supports some non-Java web application technologies, such as SHTML and CGI.

web cache. An Sun ONE Application Server feature that enables a servlet or JSP to cache its results for a specific duration in order to improve performance. Subsequent calls to that servlet or JSP within the duration are given the cached results so that the servlet or JSP does not have to execute again.

web connector plug-in. An extension to a web server that enables it to communicate with the Sun ONE Application Server.

web container. See container.

web module. An individually deployed web application. See web application.

web server. A host that stores and manages HTML pages and web applications, but not full J2EE applications. The web server responds to user requests from web browsers.

Web Server Plugin. The web server plugin is an HTTP reverse proxy plugin that allows you to instruct a Sun One Web Server or Sun ONE Application Server to forward certain HTTP requests to another server.

web service . A service offered via the web. A self-contained, self-describing, modular application that can accept a request from a system across the Internet or an intranet, process it, and return a response.

WSDL. Web Service Description Language. An XML-based language used to define web services in a standardized way. It essentially describes three fundamental properties of a web service: definition of the web service, how to access that web service, and the location of that web service.

UDDI. Universal Description, Discovery, and Integration. Provides worldwide registry of web services for discovery and integration.

XA protocol. A database industry standard protocol for distributed transactions.

XML. Extensible Markup Language. A language that uses HTML-style tags to identify the kinds of information used in documents as well as to format documents.