J2EE Interview questions and answers

321. What is Web component 

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

322. What is Web container 

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


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. 

324. What is Web container provider 

A vendor that supplies a Web container. 

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. 

326. What is Web resource 

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


327. What is Web resource collection 

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

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 as
CGI scripts or servlets) that perform certain
functions. In the J2EE architecture, a Web server
provides services to a Web container. For example, a
Web 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. 


329. What is Web server provider 

A vendor that supplies a Web server. 

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.