Skills required for Sun test 310-090

Understanding the programming restrictions that apply to EJB 2.0. Identifying the requirements and responsibilities of the EJB container in providing various services. Writing code for EJB applications that include remote home, remote component, local home, and local component interfaces.......
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Things to practice for Sun test CX310-090

The CX310-090(Sun Certified Business Component Developer for the Java 2 Platform, Enterprise Edition 1.3) test checks your ability to understand, test, and develop basic EJB codes. It requires you to have a good understanding of enterprise Java beans 2.0, and the ability to write code for......
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EJB programming restrictions

An enterprise bean works best when it follows the EJB programming restrictions. A bean provider must follow these to ensure that the enterprise bean is portable and can be deployed in any compliant EJB 2.0 container. If a bean class does not follow these restrictions, it will still work. However,......
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EJB Transaction

A transaction is a unit of work that consists of a group of activities performed as a unit such that either all or none of them succeed. An example of where transactions could take place is an online bookstore. In an online bookstore, the purchasing of books involves the following steps: A......
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How to deploy and run an EJB application using a J2EE server.

Take the following steps to deploy and run an EJB application using a J2EE server. Write code for a Remote interface and save the file as Welcome.java. The code for Welcome.java is given below: import javax.ejb.*; import java.rmi.RemoteException; public interface Welcome extends......
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Describe the life cycle of a message-driven bean.

The life cycle of a message-driven bean has two states, namely the 'does not exist' and 'pooled' state. A message-driven bean does not maintain any client specific state. It does not have the home and component interfaces. The following image shows the life cycle of a message-driven bean:......
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Describe the life cycle of a stateful session bean.

The life cycle of a stateful session bean is shown in the following image: A stateful session bean can have three states during its life as follows: Does not exist Method ready Passivated A client invokes the create() method of the stateful session bean. As a result, the container......
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Describe the life cycle of a stateless session bean.

A stateless session bean does not maintain any client specific information. It has only two states in its life cycle as shown below: Does not exist Method ready The container creates instances of a stateless session bean and keeps them in a pool of instances. When there is a method......
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Describe the life cycle of an entity bean.

The life cycle of an entity bean is as shown in the following image: An entity bean can have three states during its life as follows: Does not exist Pooled Method ready In the does not exist state, the bean instance has not yet been created. To start an entity bean's life cycle,......
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How does the JNDI locate the home interface of an enterprise bean?

To locate the home interface of an enterprise bean, the JNDI requires the following steps: Create the JNDI naming context using the InitialContext class as follows: Context ctx = new InitialContext() Use the InitialContext reference to look up for the JNDI name as follows:......
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