Java n J2ee Q&A: 2007

Tuesday, November 6, 2007

Saturday, October 6, 2007

346. What is component (JavaServer Faces technology)

A user interface control that outputs data to a clientor allows a user to input data to a JavaServer Faces application.

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345. What is binary entity

A general entity that contains something other than XML. By its nature, an unparsed entity contains binary data.

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344. What is XSLTC

A compiling version of XSLT.

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XSL Transformations. An XML document that controls the transformation of an XML document into another XML document or HTML. The target document often has presentation-related tags dictating how it will be rendered by a browser or other presentation mechanism. XSLT was formerly a part of XSL, which also included a
tag language of style flow objects.

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342. What is XSL-FO

A subcomponent of XSL used for describing font sizes, page layouts, and how information flows from one page to another.

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341. What is XSL

Extensible Style sheet Language. A standard that lets you do the following: Specify an addressing mechanism, so that you can identify the parts of an XML document that a transformation applies to (XPath). Specify tag conversions, so that you can convert XML data into different formats (XSLT). Specify display characteristics, such page sizes, margins, and font heights and widths, as well as the flow objects on each page. Information fills in one area of a page and then automatically flows to the next object when that area fills up. That allows you to wrap text around pictures, for example, or to continue a newsletter article on a different page (XSL-FO).

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340. What is XPointer

The part of the XLL specification that is concerned with identifying sections of documents so that they can be referenced in links or included in other documents.

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339. What is XPath

An addressing mechanism for identifying the parts of an XML document.

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338. What is XML Schema

The W3C specification for defining the structure, content, and semantics of XML documents.

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337. What is XML registry

An infrastructure that enables the building, deployment, and discovery of Web services. It is a neutral third party that facilitates dynamic and loosely coupled business-to-business (B2B) interactions.

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336. What is XML

Extensible Markup Language. A markup language that allows you to define the tags (markup) needed to identify the content, data, and text in XML documents. It differs from HTML, the markup language most often used to present information on the Internet. HTML has fixed tags that deal mainly with style or presentation. An XML document must undergo a transformation into a language with style tags under the control of a style sheet before it can be presented by a browser or other presentation mechanism. Two types of style sheets used with XML are CSS and XSL. Typically, XML is transformed into HTML for presentation. Although tags can be defined as needed in the generation of an XML document, a document type definition (DTD) can be used to define the elements allowed in a particular type of document. A document can be compared by using the rules in the DTD to determine its validity and to locate particular elements in the document. A Web services application'sJ2EE deployment descriptors are expressed in XML with schemas defining allowed elements. Programs for processing XML documents use SAX or DOM APIs.

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335. What is XLL

The XML Link Language specification, consisting ofXLink and XPointer.

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334. What is XLink

The part of the XLL specification that is concerned with specifying links between documents.

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333. What is XHTML

An XML look-alike for HTML defined by one of several XHTML DTDs. To use XHTML for everything would of course defeat the purpose of XML, because the idea ofXML is to identify information content, and not just
to tell how to display it. You can reference it in aDTD, which allows you to say, for example, that the text in an element can contain < em > and < b > tags rather than being limited to plain text.

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332. What is Xalan

An interpreting version of XSLT.

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331. What is well-formed

An XML document that is syntactically correct. It does not have any angle brackets that are not part of tags, all tags have an ending tag or are themselves self-ending, and all tags are fully nested. Knowing that a document is well formed makes it possible to process it. However, a well-formed document may not be valid. To determine that, you need a validating parser and a DTD.

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330. What is Web service

An application that exists in a distributed environment, such as the Internet. A Web service accepts a request, performs its function based on the request, and returns a response. The request and the response can be part of the same operation, or they can occur separately, in which case the consumer does not need to wait for a response. Both the request and the response usually take the form of XML, a portable data-interchange format, and are delivered over a wire protocol, such as HTTP.

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329. What is Web server provider

A vendor that supplies a Web server.

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328. What is Web server

Software that provides services to access the Internet, an intranet, or an extranet. A Web server hosts Web sites, provides support for HTTP and other protocols, and executes server-side programs (such asCGI scripts or servlets) that perform certain functions. In the J2EE architecture, a Web server provides services to a Web container. For example, aWeb container typically relies on a Web server to provide HTTP message handling. The J2EE architecture assumes that a Web container is hosted by a Web server from the same vendor, so it does not specify the contract between these two entities. A Web server can host one or more Web containers.

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327. What is Web resource collection

A list of URL patterns and HTTP methods that describe a set of Web resources to be protected.

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326. What is Web resource

A static or dynamic object contained in a Web application that can be referenced by a URL.

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325. What is Web module

A deployable unit that consists of one or more Web components, other resources, and a Web application deployment descriptor contained in a hierarchy of directories and files in a standard Web application format.

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324. What is Web container provider

A vendor that supplies a Web container.

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323. What is Web container, distributed

A Web container that can run a Web application that is tagged as distributable and that executes across multiple Java virtual machines running on the same host or on different hosts.

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322. What is Web container

A container that implements the Web component contractof the J2EE architecture. This contract specifies a runtime environment for Web components that includessecurity, concurrency, life-cycle management,transaction, deployment, and other services. A Webcontainer provides the same services as a JSPcontainer as well as a federated view of the J2EEplatform APIs. A Web container is provided by a Web or J2EE server.

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321. What is Web component

A component that provides services in response to requests; either a servlet or a JSP page.

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320. What is Web application, distributable

A Web application that uses J2EE technology written so that it can be deployed in a Web container distributed across multiple Java virtual machines running on the same host or different hosts. The deployment descriptor for such an application uses the distributable element.

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319. What is Web application

An application written for the Internet, including those built with Java technologies such as Java Server Pages and servlets, as well as those built with non-Java technologies such as CGI and Perl.

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318. What is warning

A SAX parser warning is generated when the document's DTD contains duplicate definitions and in similar situations that are not necessarily an error but which the document author might like to know about, because
they could be. See also fatal error, error.

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317. What is WAR file

Web application archive file. A JAR archive that contains a Web module.

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316. What is W3C

World Wide Web Consortium. The international body that governs Internet standards.

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315. What is virtual host

Multiple hosts plus domain names mapped to a single IPaddress.

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314. What is value-binding _expression

A Java Server Faces EL _expression that refers to a property of a backing bean. A component tag uses this _expression to bind the associated component's value or the component instance to the bean property. If the component tag refers to the property via its value attribute, then the component's value is bound to the property. If the component tag refers to the property via its binding attribute then the component itself is bound to the property.

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313. What is validating parser

A parser that ensures that an XML document is valid in addition to being well formed. See also parser.

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312. What is user (security)

A valid XML document, in addition to being well formed, conforms to all the constraints imposed by a DTD. It does not contain any tags that are not permitted by the DTD, and the order of the tags conforms to the DTD's specifications.

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311. What is user (security)

An individual (or application program) identity that has been authenticated. A user can have a set of roles
associated with that identity, which entitles the user to access all resources protected by those roles.

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Sunday, September 16, 2007

300. What is transaction

An atomic unit of work that modifies data. A transaction encloses one or more program statements, all of which either complete or roll back. Transactions enable multiple users to access the same data concurrently.

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299. What is transaction attribute

A value specified in an enterprise bean's deployment descriptor that is used by the EJB container to control the transaction scope when the enterprise bean's methods are invoked. A transaction attribute can have the following values: Required, Requires New, Supports, Not Supported, Mandatory, or Never.

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298. What is tool provider

An organization or software vendor that provides tools used for the development, packaging, and deployment ofJ2EE applications.

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297. What is template

A set of formatting instructions that apply to the nodes selected by an X Path _expression .

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296. What is tag

In XML documents, a piece of text that describes a unit of data or an element. The tag is distinguishable markup, as opposed to data, because it is surrounded by angle brackets (< and >). To treat such markup syntax as data, you use an entity reference ora CDATA section.

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295. What is system administrator

The person responsible for configuring and administering the enterprise's computers, networks, and software systems.

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294. What is stateless session bean

A session bean with no conversational state. All instances of a stateless session bean are identical.

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293. What is stateful session bean

A session bean with a conversational state.

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292. What is SSL

Secure Socket Layer. A security protocol that providesprivacy over the Internet. The protocol allowsclient-server applications to communicate in a waythat cannot be eavesdropped upon or tampered with.Servers are always authenticated, and clients areoptionally authenticated.

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291. What is SQL/J

A set of standards that includes specifications for embedding SQL statements in methods in the Java programming language and specifications for calling Java static methods as SQL stored procedures and user-defined functions. An SQL checker can detect errors in static SQL statements at program development time, rather than at execution time as with a JDBC driver.

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290. What is SQL

Structured Query Language. The standardized relational database language for defining database objects and manipulating data.

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289. What is SOAP with Attachments API for Java (SAAJ)

The basic package for SOAP messaging, SAAJ contains the API for creating and populating a SOAP message.

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288. What is SOAP

Simple Object Access Protocol. A lightweight protocol intended for exchanging structured information in a decentralized, distributed environment. It defines, using XML technologies, an extensible messaging framework containing a message construct that can be exchanged over a variety of underlying protocols.

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287. What is SGML

Standard Generalized Markup Language. The parent of both HTML and XML. Although HTML shares SGML's propensity for embedding presentation information in the markup, XML is a standard that allows information content to be totally separated from the mechanisms for rendering that content.

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286. What is session bean

An enterprise bean that is created by a client and that usually exists only for the duration of a single client-server session. A session bean performs operations, such as calculations or database access, for the client. Although a session bean can be transactional, it is not recoverable should a system crash occur. Session bean objects either can be stateless or can maintain conversational state across methods and transactions. If a session bean maintains state, then the EJB container manages this state if the object must be removed from memory. However, the session bean object itself must manage its own persistent data.

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285. What is session

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

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284. What is servlet mapping

Defines an association between a URL pattern and a servlet. The mapping is used to map requests to servlets.

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283. What is servlet context

An object that contains a servlet's view of the Web application within which the servlet is running. Using the context, a servlet can log events, obtain URL references to resources, and set and store attributes that other servlets in the context can use.

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282. What is servlet container, distributed

A servlet container that can run a Web application that is tagged as distributable and that executes across multiple Java virtual machines running on the same host or on different hosts.

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281. What is servlet container

A container that provides the network services over which requests and responses are sent, decodes requests, and formats responses. All servlet containers must support HTTP as a protocol for requests and responses but can also support additional request-response protocols, such as HTTPS.

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280. What is servlet

A Java program that extends the functionality of a Web server, generating dynamic content and interacting with Web applications using a request-response paradigm.

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279. What is service endpoint interface

A Java interface that declares the methods that a client can invoke on a Web service.

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278. What is service element

A representation of the combination of one or more Connector components that share a single engine component for processing incoming requests.

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277. What is server principal

The OS principal that the server is executing as.

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276. What is server certificate

Used with the HTTPS protocol to authenticate Web applications. The certificate can be self-signed or approved by a certificate authority (CA). The HTTPS service of the Sun Java System Application Server Platform Edition 8 will not run unless a server certificate has been installed.

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275. What is security view

The set of security roles defined by the application assembler.

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274. What is security technology domain

A scope over which the same security mechanism is used to enforce a security policy. Multiple security policy domains can exist within a single technology domain.

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273. What is security role

An abstract logical grouping of users that is defined by the application assembler. When an application is deployed, the roles are mapped to security identities, such as principals or groups, in the operational environment. In the J2EE server authentication service, a role is an abstract name for permission to access a particular set of resources. A role can be compared to a key that can open a lock. Many people might have a copy of the key; the lock doesn't care who you are, only that you have the right key.

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272. What is security policy domain

A scope over which security policies are defined and enforced by a security administrator. A security policy domain has a collection of users (or principals), uses a well-defined authentication protocol or protocols for authenticating users (or principals), and may have groups to simplify setting of security policies.

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271. What is security permission set

The minimum set of security permissions that a J2EEproduct provider must provide for the execution of each component type.

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270. What is security permission

A mechanism defined by J2SE, and used by the J2EEplatform to express the programming restrictions imposed on application component developers.

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269. What is security context

An object that encapsulates the shared state information regarding security between two entities.

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268. What is security constraint

A declarative way to annotate the intended protection of Web content. A security constraint consists of a Web resource collection, an authorization constraint, and a user data constraint.

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267. What is security attributes

A set of properties associated with a principal. Security attributes can be associated with a principal by an authentication protocol or by a J2EE product provider or both.

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268. What is Secure Socket Layer (SSL)

A technology that allows Web browsers and Web servers to communicate over a secured connec tion.

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267. What is schema

A database-inspired method for specifying constraintson XML documents using an XML-based language. Schemasaddress deficiencies in DTDs, such as the inability toput constraints on the kinds of data that can occur ina particular field. Because schemas are founded onXML, they are hierarchical. Thus it is easier tocreate an unambiguous specification, and it ispossible to determine the scope over which a commentis meant to apply.

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266. What is Simple API for XML

An event-driven interface in which the parser invokes one of several methods supplied by the caller when a parsing event occurs. Events include recognizing anXML tag, finding an error, encountering a reference toan external entity, or processing a DTD specification.

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Thursday, September 13, 2007

265. What is SAX

Abbreviation of Simple API for XML.

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264. What is root

The outermost element in an XML document. The element that contains all other elements.

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263. What is rollback

The point in a transaction when all updates to any resources involved in the transaction are reversed.

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262. What is role (security)

261. What is role mapping

The process of associating the groups or principals(or both), recognized by the container with security roles specified in the deployment descriptor. Security roles must be mapped by the deployer before a component is installed in the server.

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260. What is role (development)

The function performed by a party in the development and deployment phases of an application developed using J2EE technology. The roles are application component provider, application assembler, deployer,J2EE product provider, EJB container provider, EJB server provider, Web container provider, Web server provider, tool provider, and system administrator.

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259. What is RMI-IIOP

A version of RMI implemented to use the CORBA IIOP protocol. RMI over IIOP provides interoperability with CORBA objects implemented in any language if all there mote interfaces are originally defined as RMI interfaces.

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258. What is RMI

Remote Method Invocation. A technology that allows an object running in one Java virtual machine to invoke methods on an object running in a different Java virtual machine.

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257. What is resource manager connection factory

An object used for creating a resource manager connection.

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256. What is resource manager connection

An object that represents a session with a resource manager.

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255. What is resource manager

Provides access to a set of shared resources. A resource manager participates in transactions that are externally controlled and coordinated by a transaction manager. A resource manager typically is in a different address space or on a different machine from the clients that access it. Note: An enterprise information system is referred to as a resource manager when it is mentioned in the context of resource and transaction management.

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254. What is resource adapter module

A deployable unit that contains all Java interfaces, classes, and native libraries, implementing a resource adapter along with the resource adapter deployment descriptor.

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253. What is resource adapter

A system-level software driver that is used by an EJB container or an application client to connect to an enterprise information system. A resource adapter typically is specific to an enterprise information system. It is available as a library and is used within the address space of the server or client using it. A resource adapter plugs in to a container. The application components deployed on the container then use the client API (exposed by the adapter) or tool-generated high-level abstractions to access the underlying enterprise information system. The resource adapter and EJB container collaborate to provide the underlying mechanisms-transactions, security, and connection pooling-for connectivity to the enterprise information system.

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252. What is request-response messaging

A method of messaging that includes blocking until a response is received.

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251. What is renderer

A Java class that can render the output for a set of Java Server Faces UI components.

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250. What is render kit

A set of renderers that render output to a particular client. The Java Server Faces implementation provides a standard HTML render kit, which is composed ofrenderers that can render HMTL markup.

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249. What is remove method

Method defined in the home interface and invoked by a client to destroy an enterprise bean.

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248. What is remote interface

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

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247. What is relationship field

A virtual field of an entity bean having container-managed persistence; it identifies a related entity bean.

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246. What is registry provider

An implementation of a business registry that conforms to a specification for XML registries (for example, ebXML or UDDI).

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245. What is registry

244. What is reference

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 < 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.

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243. What is reentrant entity bean

An entity bean that can handle multiple simultaneous, interleaved, or nested invocations that will not interfere with each other.

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242. What is realm

See security policy domain. Also, a string, passed as part of an HTTP request during basic authentication, that defines a protection space. The protected resources on a server can be partitioned into a set of protection spaces, each with its own authentication scheme or authorization database or both. In the J2EEserver authentication service, a realm is a complete database of roles, users, and groups that identify valid users of a Web application or a set of Web applications.

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241. What is RDF schema

A standard for specifying consistency rules that apply to the specifications contained in an RDF.

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240. What is RDF

Resource Description Framework. A standard for defining the kind of data that an XML file contains. Such information can help ensure semantic integrity-for example-by helping to make sure that a date is treated as a date rather than simply as text.

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239. What is RAR

Resource Adapter Archive. A JAR archive that contains a resource adapter module.

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238. What is queue

A messaging system built on the concept of message queues. Each message is addressed to a specific queue; clients extract messages from the queues established to hold their messages.

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237. What is query string

A component of an HTTP request URL that contains a setoff parameters and values that affect the handling of the request.

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236. What is publish/subscribe messaging system

A messaging system in which clients address messages to a specific node in a content hierarchy, called a topic. Publishers and subscribers are generally anonymous and can dynamically publish or subscribe to the content hierarchy. The system takes care of distributing the messages arriving from a node's multiple publishers to its multiple subscribers.

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235. What is public key certificate

Used in client-certificate authentication to enable the server, and optionally the client, to authenticate each other. The public key certificate is the digital equivalent of a passport. It is issued by a trusted organization, called a certificate authority, and provides identification for the bearer.

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Monday, September 10, 2007

234. What is prolog

The part of an XML document that precedes the XMLdata. The prolog includes the declaration and an optional DTD.

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233. What is programmatic security

Security decisions that are made by security-aware applications. Programmatic security is useful when declarative security alone is not sufficient to express the security model of an application

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232. What is processing instruction

Information contained in an XML structure that is intended to be interpreted by a specific application.

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231. What is privilege

A security attribute that does not have the property of uniqueness and that can be shared by many principals.

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230. What is principal

The identity assigned to a user as a result of authentication.

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229. What is primary key

An object that uniquely identifies an entity bean within a home.

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227. What is point-to-point messaging system

226. What is POA

Portable Object Adapter. A CORBA standard for building server-side applications that are portable across heterogeneous ORBs.

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225. What is persistent field

A virtual field of an entity bean that has container-managed persistence; it is stored in a database.

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224. What is persistence

The protocol for transferring the state of an entity bean between its instance variables and an underlying database.

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223. What is passivation

The process of transferring an enterprise bean from memory to secondary storage. See activation.

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222. What is parser

A module that reads in XML data from an input source and breaks it into chunks so that your program knows when it is working with a tag, an attribute, or element data. A no validating parser ensures that the XML data is well formed but does not verify that it is valid. See also validating parser.

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221. What is parsed entity

A general entity that contains XML and therefore is parsed when inserted into the XML document, as opposed to an unparsed entity.

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220. What is parameter entity

An entity that consists of DTD specifications, as distinct from a general entity. A parameter entity defined in the DTD can then be referenced at other points, thereby eliminating the need to recode the definition at each location it is used.

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209. What is OTS

Object Transaction Service. A definition of the interfaces that permit CORBA objects to participate in transactions.

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208. What is OS principal

A principal native to the operating system on which the J2EE platform is executing.

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207. What is ORB

Object request broker. A library that enables CORBA objects to locate and communicate with one another.

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206. What is one-way messaging

A method of transmitting messages without having to block until a response is received.

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205. What is OMG

Object Management Group. A consortium that produces and maintains computer industry specifications for interoperable enterprise applications.

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204. What is OASIS

Organization for the Advancement of Structured Information Standards. A consortium that drives the development, convergence, and adoption of e-business standards.

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203. What is notation

A mechanism for defining a data format for a non-XML document referenced as an unparsed entity. This is a holdover from SGML. A newer standard is to use MIME data types and namespaces to prevent naming conflicts.

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202. What is North American Industry Classification System (NAICS)

A system for classifying business establishments based on the processes they use to produce goods or services.

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201. What is normalization

The process of removing redundancy by modularizing, as with subroutines, and of removing superfluous differences by reducing them to a common denominator. For example, line endings from different systems are normalized by reducing them to a single new line, and multiple white space characters are normalized to one space.

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200. What is naming environment

A mechanism that allows a component to be customized without the need to access or change the component's source code. A container implements the component's naming environment and provides it to the component as a JNDI naming context. Each component names and accesses its environment entries using the
java:comp/env JNDI context. The environment entries are declaratively specified in the component's deployment descriptor.

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199. What is naming context

A set of associations between unique, atomic, people-friendly identifiers and objects.

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198. What is namespace

A standard that lets you specify a unique label for the set of element names defined by a DTD. A document using that DTD can be included in any other document without having a conflict between element names. The elements defined in your DTD are then uniquely identified so that, for example, the parser can tell when an element should be interpreted according to your DTD rather than using the definition for an element in a different DTD

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197. What is mutual authentication

An authentication mechanism employed by two parties for the purpose of proving each other's identity to one another.

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196. What is method permission

An authorization rule that determines who is permitted to execute one or more enterprise bean methods.

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195. What is method-binding _expression

A Java Server Faces EL _expression that refers to a method of a backing bean. This method performs either event handling, validation, or navigation processing for the UI component whose tag uses the method-binding _expression.

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194. What is mixed-content model

A DTD specification that defines an element as containing a mixture of text and one more other elements. The specification must start with #PCDATA, followed by diverse elements, and must end with the"zero-or-more" asterisk symbol (*).

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193. What is message producer

An object created by a JMS session that is used for sending messages to a destination.

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192. What is 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 can 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 bean is a message listener.

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191. What is message consumer

An object created by a JMS session that is used for receiving messages sent to a destination.

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190. What is message

In the Java Message Service, an asynchronous request, report, or event that is created, sent, and consumed by an enterprise application and not by a human. It contains vital information needed to coordinate enterprise applications, in the form of precisely formatted data that describes specific business actions.

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189. What is managed bean creation facility

A mechanism for defining the characteristics of JavaBeans components used in a Java Server Faces application.

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188. What is local subset

That part of the DTD that is defined within the current XML file.

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187. What is life cycle (JavaServer Faces)

A set of phases during which a request for a page is received, a UI component tree representing the page is processed, and a response is produced. During the phases of the life cycle: The local data of the components is updated with the values contained in the request parameters. Events generated by the components are processed. Valuators and converters registered on the components are processed. The components' local data is updated to back-end objects. The response is rendered to the client while the component state of the response is saved on the server for future requests.

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186. What is life cycle (J2EE component)

The framework events of a J2EE component's existence. Each type of component has defining events that mark its transition into states in which it has varying availability for use. For example, a servlet is created and has its init method called by its container before invocation of its service method by clients or other servlets that require its functionality. After the call of its init method, ithas the data and readiness for its intended use. The servlet's destroy method is called by its container before the ending of its existence so that processing associated with winding up can be done and resource scan be released. The init and destroy methods in this example are callback methods. Similar considerations apply to the life cycle of all J2EE component types: enterprise beans, Web components (servlets or JSP pages), applets, and application clients.

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185. What is keystore

A file containing the keys and certificates used for authentication

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184. What is JTS

Abbreviate of Java Transaction Service.
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183. What is JTA

Abbreviate of Java Transaction API.

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182. What is JSTL

Abbreviate of Java Server Pages Standard Tag Library.

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181. What is JSP tag library

A collection of custom tags described via a tag
library descriptor and Java classes.

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180. What is JSP tag handler

A Java programming language object that implements the behavior of a custom tag.

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179. What is JSP tag file

A source file containing a reusable fragment of JSP code that is translated into a tag handler when a JSP page is translated into a servlet.

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178. What is JSP standard action

An action that is defined in the JSP specification and is always available to a JSP page.

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177. What is JSP scriptlet

A JSP scripting element containing any code fragment that is valid in the scripting language used in the JSP page. The JSP specification describes what a valid scriptlet for the case is where the language page attribute is "java".

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176. What is JSP scripting element

A JSP declaration, script let, or _expression whose syntax is defined by the JSP specification and whose content is written according to the scripting language used in the JSP page. The JSP specification describes the syntax and semantics for the case where the language page attribute is "java".

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175. What is JSP page

A text-based document containing static text and JSP elements that describes how to process a request to create a response. A JSP page is translated into and handles requests as a servlet.

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174. What is JSP _expression language?

A language used to write expressions that access the properties of JavaBeans components. EL expressions can be used in static text and in any standard or custom tag attribute that can accept an _expression.

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Sunday, September 9, 2007

173. What is JSP _expression

A scripting element that contains a valid scripting language _expression that is evaluated, converted to a String, and placed into the implicit out object.

172. What is JSP element

A portion of a JSP page that is recognized by a JSP translator. An element can be a directive, an action, or a scripting element.

171. What is JSP document

A JSP page written in XML syntax and subject to the constraints of XML documents.

170. What is JSP directive

A JSP element that gives an instruction to the JSPcontainer and is interpreted at translation time.

169. What is JSP declaration

A JSP scripting element that declares methods, variables, or both in a JSP page.

168. What is JSP custom tag

A tag that references a JSP custom action.

167. What is JSP custom action

A user-defined action described in a portable mannerby a tag library descriptor and imported into a JSP page by a taglib directive. Custom actions are used toencapsulate recurring tasks in writing JSP pages.

165. What is JSP container, distributed

A JSP container that can run a Web application that istagged as distributable and is spread across multiple Java virtual machines that might be running ondifferent hosts.

164. What is JSP container

A container that provides the same services as aservlet container and an engine that interprets and processes JSP pages into a servlet.

163. What is JSP action

A JSP element that can act on implicit objects and other server-side objects or can define new scripting variables. Actions follow the XML syntax for elements, with a start tag, a body, and an end tag; if the body is empty it can also use the empty tag syntax. The tagmust use a prefix. There are standard and custom actions.

162. What is JSP

Abbreviate of Java Server Pages.

161. What is JNDI

Abbreviate of Java Naming and Directory Interface.

160. What is JMS session

A single-threaded context for sending and receiving JMS messages. A JMS session can be no transacted, locally transacted, or participating in a distributed transaction.

159. What is JMS provider

A messaging system that implements the Java Message Service as well as other administrative and control functionality needed in a full-featured messaging product.

158. What is JMS client

A Java language program that sends or receives
messages.

157. What is JMS application

One or more JMS clients that exchange messages.

156. What is JMS administered object

A preconfigured JMS object (a resource manager connection factory or a destination) created by an administrator for the use of JMS clients and placed ina JNDI namespace

155. What is JMS

Java Message Service.

154. What is JDBC

An JDBC for database-independent connectivity between the J2EE platform and a wide range of data sources.

153. What is JAXR provider

An implementation of the JAXR API that provides access to a specific registry provider or to a class of registry providers that are based on a common specification.

152. What is JAXR client

A client program that uses the JAXR API to access a business registry via a JAXR provider.

151. What is Java Server Pages Standard Tag Library (JSTL)

A tag library that encapsulates core functionality common to many JSP applications. JSTL has support for common, structural tasks such as iteration and conditionals, tags for manipulating XML documents, internationalization and locale-specific formatting tags, SQL tags, and functions.

150. What is Java Server Pages (JSP)

An extensible Web technology that uses static data, JSP elements, and server-side Java objects to generate dynamic content for a client. Typically the static data is HTML or XML elements, and in many cases the client is a Web browser.

149. What is Java Server Faces validation model

A mechanism for validating the data a user inputs to aJavaServer Faces UI component.

148. What is Java Server Faces UI component class

A Java Server Faces class that defines the behavior and properties of a Java Server Faces UI component.

147. What is Java Server Faces UI component

A user interface control that outputs data to a client allows a user to input data to a Java Server Faces application.

145. What is Java Server Faces navigation model

A mechanism for defining the sequence in which pages in a Java Server Faces application are displayed.

144. What is Java Server Faces _expression language

A simple _expression language used by a Java Server Faces UI component tag attributes to bind the associated component to a bean property or to bind the associated component's value to a method or an external data source, such as a bean property. Unlike EL expressions, Java Server Faces EL expressions are evaluated by the Java Server Faces implementation rather than by the Web container.

143. What is Java Server Faces event and listener model

A mechanism for determining how events emitted byJavaServer Faces UI components are handled. This model is based on the JavaBeans component event and listener model.

142. What is Java Server Faces conversion model

A mechanism for converting between string-based markup generated by Java Server Faces UI components and server-side Java objects.

141. What is Java Server Faces Technology

A framework for building server-side user interfaces for Web applications written in the Java programming language.

140. What is Java Mail

An API for sending and receiving email.

139. What is JavaBeans component

A Java class that can be manipulated by tools and composed into applications? A JavaBeans component must adhere to certain property and event interface conventions.

138. What is Java Transaction Service (JTS)

Specifies the implementation of a transaction manager that supports JTA and implements the Java mapping of the Object Management Group Object Transaction Service1.1 specification at the level below the API.

137. What is Java Transaction API (JTA)

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

136. What is Java Secure Socket Extension (JSSE)

A set of packages that enable secure Internet communications.

135. What is Java Naming and Directory Interface (JNDI)

An API that provides naming and directory functionality.

134. What is Java Message Service (JMS)

An API for invoking operations on enterprise messaging systems.

133. What is Java IDL

A technology that provides CORBA interoperability and connectivity capabilities for the J2EE platform. These capabilities enable J2EE applications to invoke operations on remote network services using the Object Management Group IDL and IIOP.

132. What is Java API for XML-based RPC (JAX-RPC)

An API for building Web services and clients that use remote procedure calls and XML

130. What is Java API for XML Processing (JAXP)

An API for processing XML documents. JAXP leverages the parser standards SAX and DOM so that you can choose to parse your data as a stream of events or to build a tree-structured representation of it. JAXP supports the XSLT standard, giving you control over the presentation of the data and enabling you to convert the data to other XML documents or to other formats, such as HTML. JAXP provides namespace support, allowing you to work with schema that might otherwise have naming conflicts.

129. What is Java 2 Platform, Standard Edition (J2SE)

The core Java technology platform.

128. What is Java 2 Platform, Micro Edition (J2ME)

A highly optimized Java runtime environment targeting a wide range of consumer products, including pagers, cellular phones, screen phones, digital set-top boxes, and car navigation systems.

127. What is Java 2 Platform, Enterprise Edition

127. What is Java 2 Platform, Enterprise Edition
(J2EE)
An environment for developing and deploying enterprise applications. The J2EE platform consists of a set of services, application programming interfaces (APIs),and protocols that provide the functionality for developing multitiered, Web-based applications.

126. What is JAR

Java archive. A platform-independent file format that permits many files to be aggregated into one file.

125. What is J2SE

Abbreviate of Java 2 Platform, Standard Edition.

124. What is J2ME

Abbreviate of Java 2 Platform, Micro Edition.

123. What is J2EE server

The runtime portion of a J2EE product. A J2EE server provides EJB or Web containers or both.

122. What is J2EE product provider

A vendor that supplies a J2EE product.

121. What is J2EE product

An implementation that conforms to the J2EE platform specification.

Friday, September 7, 2007

120. What is J2EE module

A software unit that consists of one or more J2EEcomponents of the same container type and one deployment descriptor of that type. There are four types of modules: EJB, Web, application client, and resource adapter. Modules can be deployed asstand-alone units or can be assembled into a J2EEapplication.

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119. What is J2EE component

A self-contained functional software unit supported bya container and configurable at deployment time. TheJ2EE specification defines the following J2EEcomponents: Application clients and applets are components that run on the client. Java servlet and Java Server Pages (JSP) technology components are Web components that run on the server. Enterprise JavaBeans (EJB) components (enterprise beans) are business components that run on the server. J2EEcomponents are written in the Java programming language and are compiled in the same way as any program in the language. The difference between J2EEcomponents and "standard" Java classes is that J2EEcomponents are assembled into a J2EE application, verified to be well formed and in compliance with theJ2EE specification, and deployed to production, where they are run and managed by the J2EE server or client container.

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118. What is J2EE application

Any deployable unit of J2EE functionality. This can bea single J2EE module or a group of modules packaged into an EAR file along with a J2EE application deployment descriptor. J2EE applications are typically engineered to be distributed across multiple computing tiers.

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117. What is J2EE

Java 2 Platform, Enterprise Edition.

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116. What is ISV

Independent software vendor.

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115. What is ISO 3166

The international standard for country codes maintained by the International Organization for
Standardization (ISO).

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114. What is initialization parameter

A parameter that initializes the context associated with a servlet

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113. What is impersonation

An act whereby one entity assumes the identity and privileges of another entity without restrictions and without any indication visible to the recipients of the impersonator's calls that delegation has taken place. Impersonation is a case of simple delegation.

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112. What is IIOP

Internet Inter-ORB Protocol. A protocol used for communication between CORBA object request brokers.

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111. What is IDL

Interface Definition Language. A language used to define interfaces to remote CORBA objects. The interfaces are independent of operating systems and programming languages.

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110. What is HTTPS

HTTP layered over the SSL protocol

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109. What is HTTP

Hypertext Transfer Protocol. The Internet protocol used to retrieve hypertext objects from remote hosts. HTTP messages consist of requests from client to server and responses from server to client.

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108. What is HTML

Hypertext Markup Language. A markup language for hypertext documents on the Internet. HTML enables the embedding of images, sounds, video streams, form fields, references to other objects with URLs, and basic text formatting.

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107. What is home interface

One of two interfaces for an enterprise bean. The home interface defines zero or more methods for managing an enterprise bean. The home interface of a session bean defines create and remove methods, whereas the home interface of an entity bean defines create, finder, and remove methods.

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105. What is home handle

An object that can be used to obtain a reference to the home interface. A home handle can be serialized and written to stable storage and deserialized to obtain the reference.

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104. What is handle

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

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103. What is group

An authenticated set of users classified by common traits such as job title or customer profile. Groups are also associated with a set of roles, and every user that is a member of a group inherits all the roles assigned to that group.

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102. What is general entity

An entity that is referenced as part of an XML document's content, as distinct from a parameter entity, which is referenced in the DTD. A general entity can be a parsed entity or an unparsed entity.

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101. What is form-based authentication

An authentication mechanism in which a Web container provides an application-specific form for logging in. This form of authentication uses Base64 encoding and can expose user names and passwords unless all connections are over SSL.

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