Java Database Connectivity API

The JavaDatabase Connectivity (JDBC) API lets you invoke
SQL commands from Javaprogramming language methods.
You use the JDBC API in an enterprise bean when you have a
session bean access the database. You can also use the JDBC API
from a servlet or a JSP page to access the database directly
without going through an enterprise bean.
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Java API for XML Processing

The Java API for XML Processing (JAXP), part of the Java SE platform,
supports the processing of XML documents using Document ObjectModel (DOM),
Simple API for XML (SAX), and Extensible Stylesheet Language Transformations (XSLT).
JAXP enables applications to parse and transform XML documents independent
of a particular XML processing implementation.

Enterprise JavaBeansTechnology(simply)

An EJB component,or enterprise bean, is a body of code having fieldsand methods to implement modules of business logic. You can think of an enterprise bean as abuilding block that can be used alone or with other enterprise beans to execute business logic onthe Java EE server.


There are two kinds of enterprise beans:
session beans
message-driven beans

Java EE Application Assembly and Deployment..

A Java EE application is packaged into one or more standard units for deployment to any JavaEE platform-compliant system.

Each unit contains:
¦ A functional component or components (such as an enterprise bean, JSP page, servlet, orapplet)
¦ An optional deployment descriptor that describes its content


A Java EE application is delivered in an Enterprise Archive (EAR) file, a standard Java Archive(JAR) file with an .ear extension. Using EAR files and modules makes it possible to assemble a number of different Java EE applications using some of the same components.

An EAR file contains Java EE modules and deployment descriptors. Adeployment descriptor is an XML document with an .xml extension that describes thedeployment settings of an application, a module, or a component.

Java EE components:

There are web, enterprise bean, or application clientcomponents.

¦ Application clients and applets are components that run on the client.
¦ Java Servlet, JavaServer Faces, and JavaServer Pages(JSP) technology components areweb components that run on the server.
¦ Enterprise JavaBeans(EJB) components (enterprise beans) are business componentsthat run on the server.

Containers..Containers are the interface between a component and the low-level platform-specificfunctionality that supports the component. Before a web, enterprise bean, or application clientcomponent can be executed, it must be assembled into a Java EE module and deployed into its container.