J2EE for Enterprise Integration - Guide to Cloud Computing for Business and Technology Managers - page 148

6.2.4.2.2 Java Naming and Directory Interface (JNDI)
In J2EE application servers, JNDI provides via neutral APIs a mechanism that
is used by the clients, Web components, and EJBs to find J2EE resources using
a symbolic naming scheme. Directory and naming services are used to map
symbolic names or a set of search attributes onto a resource. For example,
the Domain Name System maps symbolic host names onto their Internet
addresses. Similarly, a File System maps a symbolic pathname onto a system
file identifier like an inode in Unix. Individually, all of these naming and direc-
tory services have specific APIs and may be written in a variety of languages.
6.2.4.2.3 Java Connector Architecture (JCA)
JTS is a comprehensive service that supports distributed transactions and
consequently two-phase commit protocol.
JCA, which is a subset of JTS, is made available as a resource to J2EE
application.
6.2.4.2.4 XML Processing APIs
XML is a widely accepted way of representing data in a standard format
that can be validated against a Document Type Definition (DTD) or schema.
These data can then be transmitted between various systems that convert the
neutral format to system-specific formats, for example, to a relational form.
Just as Java provides code portability, XML provides data portability. XML is
also used as the configuration language in J2EE.
6.2.4.3 Communication Services
6.2.4.3.1 HTTP/HTTPS
Hypertext Transfer Protocol (HTTP) is a text-based protocol used for com-
munication across the Internet and supports Web browser interactions with
the HTTP servers listening on server machines. The protocol is stateless in
that the server does not maintain any client state—every request made by an
HTTP client will have to provide all essential information needed to process
the request like
• The nature of the client (e.g., kind of browser)
• The kind of request
• The resource target on the server (e.g., a particular HTML page or
servlet)
• The data to be sent to the server
Client requests are matched with server responses that provide information
about the request like