What is EJBs role in J2EE?
EJB technology is the core of J2EE. It enables developers to write reusable and portable server-side business logic for the J2EE platform.
View ArticleWhat are the different kinds of enterprise beans?
1.Stateless session bean- An instance of these non-persistent EJBs provides a service without storing an interaction or conversation state between methods. Any instance can be used for any client....
View ArticleWhat is session Facade?
Session Facade is a design pattern to access the Entity bean through local interface than accessing directly. It increases the performance over the network. In this case we call session bean which on...
View ArticleWhat technologies are included in J2EE?
The main technologies in J2EE are: Enterprise JavaBeansTM (EJBsTM), JavaServer PagesTM (JSPsTM), Java Servlets, the Java Naming and Directory InterfaceTM (JNDITM), the Java Transaction API (JTA),...
View ArticleWhat is Enterprise JavaBeans (EJB) container?
It manages the execution of enterprise beans for J2EE applications. Enterprise beans and their container run on the J2EE server.
View ArticleWhat is the new basic requirement for a CMP entity bean class in 2.0 from...
It must be abstract class. The container extends it and implements methods which are required for managing the relationships
View ArticleHow does EJB Invocation happens?
Step 1: Retrieve Home Object reference from Naming Service via JNDI. step 2: Return Home Object reference to the client. step 3: Create me a new EJB Object through Home Object interface. step 4: Create...
View ArticleWhat is the relationship between local interfaces and container-managed...
Entity beans that have container-managed relationships with other entity beans, must be accessed in the same local scope as those related beans, and therefore typically provide a local client view. In...
View ArticleAre enterprise beans allowed to use Thread.sleep()?
Enterprise beans make use of the services provided by the EJB container, such as life-cycle management. To avoid conflicts with these services, enterprise beans are restricted from performing certain...
View ArticleWhat are Local Interfaces? Describe.
EJB was originally designed around remote invocation using the Java Remote Method Invocation (RMI) mechanism, and later extended to support to standard CORBA transport for these calls using RMI/IIOP....
View ArticleWhat are transaction isolation levels in EJB?
<!--[if !supportLists]-->1. <!--[endif]-->Transaction_read_uncommitted- Allows a method to read uncommitted data from a DB(fast but not wise).<!--[if !supportLists]-->2....
View ArticleWhat is the difference between Container-Managed Persistent (CMP) bean and...
Container-managed persistence beans are the simplest for the bean developer to create and the most difficult for the EJB server to support. This is because all the logic for synchronizing the bean’s...
View ArticleWhat is bean managed transaction?
If a developer doesn’t want a Container to manage transactions, it’s possible to implement all database operations manually by writing the appropriate JDBC code. This often leads to productivity...
View ArticleWhat are transaction attributes?
The transaction attribute specifies how the Container must manage transactions for a method when a client invokes the method via the enterprise bean’s home or component interface or when the method is...
View ArticleWhat is the difference between Message Driven Beans and Stateless Session beans?
In several ways, the dynamic creation and allocation of message-driven bean instances mimics the behavior of stateless session EJB instances, which exist only for the duration of a particular method...
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