The two methods in a component are:
FormHandlers are used when there are forms. They help to perform validation for the forms.
Droplet is from ATG, and it is used to put or render data in the database.
Servlet is used to submit data, it acts as a controller. It is not used to put data.
ATG Dynamo or Dynamo Application Server(DAS) is a J2EE application server from Art Technology Group(ATG).
ATG Framework is an Application framework for building web applications.This framework contains all necessary modules and component requires for building and running ATG application. The application framework can also be run on all major J2EE application servers like JBoss,WebLogic,WebSphere etc.
a==b means that both a & b are referencing the same constant string.
Using ATG Dynamo, this is the process for entering into a Database using programs while keeping the actual application logic apart from the Database.
.ATG Repository refers to the ATG`s way of accessing the Database through programs. It is somewhat similar to what Hibernate offers, Seperating the Application Logic from that of Database. So Atg repository provides a fine grained abstraction between the application logic and Database. Thus it supports the ATG`s Data Anywhere paradigm, the application logic created by developers to interact with data need not change for any change in the source of that data. ATG repository architecture ensures that the source of the data is hidden behind the Dynamo Repository abstraction. It would be easy to change from a relational data source to another or to an LDAP directory since none of the application logic would need to change. Once data is retrieved from a data source it is transformed into an object-oriented representation. Manipulation of the data can then be done using simple getPropertyValue and setPropertyValue methods. The Repository API ties in closely with ATG’s targeting APIs, so you can retrieve items from the repository based on a variety of targeting rules, as well as retrieving specific identified items.
The core of ATG Dynamo is the nucleus which is also known as the Object Application Framework.
MVC(Modal View Controller) and IOC (Inversion of Control).
Dispatcher View Strategy (a pull based MVC) used by Droplets.
Dependency Injection or Ioc (Inversion of Control) is used by nucleus to resolve dependencies between components.
The two types of cache that ATG repository maintains(i) Item Cache
If the ATG applications are deployed on a cluster of servers then it is better to go for either Distributed caching or Locked caching.
DSP tags : DSP tag library tags support runtime expressions. These tags use an id attribute to name the scripting variables they create.
DSPEL tag : DSPEL tag library tags support JSTL Expression Language (EL) elements that are also evaluated at runtime.
The standard atg.repository.QueryBuilder interface defines available query operations that repositories should support.
In order to embed the output of a Java servlet (an ATG servlet bean) in a JSP you need to add dsp:droplet tag with a bean attribute.