EJB Home Interface & Remote Interface

EJB Home Interface

• The EJBHome object must implement the home interface.
• This interface contains the methods used by the clients to create and remove the instances of the EJB.
• The home interface is the client’s initial point of contact with your EJB components.
• For the client to access the EJB , an instance of the EJB is created from one or more create() methods of the Home interface.
• The ejbCreate() methods defined in the EJB must also be declared with matching signatures in the Home interface.
• Returns a reference to a EJB by creating or finding it.

EJB Remote Interface

• The EJBObject class must implement the remote interface.
• Once the client has used the home interface to gain access to EJB ,it uses this interface to invoke the business methods defined in the EJB class.
• Clients can never get a reference to the EJBs class , only the EJBObject class.
• The EJB container uses the remote interface for your bean to generate both the client-side stub and server-side proxy object that passes client calls to your EJB object.

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Java Deployment Descriptor

• The deployment descriptor objects are used to establish the runtime service settings for an enterprise bean
• This object defines the enviromental properties , along with the enterprise bean class name, the
• JNDI namespace,the home and remote interface name
• It has two types depending on the requirements,Session descriptor and entity descriptor
• The deployment descriptor also contains detailed inforamtion about how the bean should execute regarding transaction and security
• The deployment descriptor provides the full description of all files in the ejb jar
• Deployment descriptor is defined in a XML based format having some standard tags and attributes

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