Search results
Results From The WOW.Com Content Network
EJB QL is a database query language similar to SQL. The used queries are somewhat different from relational SQL, as it uses a so-called "abstract schema" of the enterprise beans instead of the relational model. In other words, EJB QL queries do not use tables and their components, but enterprise beans, their persistent state, and their ...
Jakarta Enterprise Beans (EJB) specification defines a set of lightweight APIs that an object container (the EJB container) will support in order to provide transactions (using JTA), remote procedure calls (using RMI or RMI-IIOP), concurrency control, dependency injection and access control for business objects. This package contains the ...
Entity Beans before EJB 2.0 should not be used in great numbers [3] because each entity bean was in fact a RMI stub with its own RMI connection to the EJB server. Obtaining 1000 entity beans as a single operation would result in 1000 simultaneous internet connections to the RMI back-end [ citation needed ] .
EJB 3.2.6, final release (2019-08-23) Jakarta Enterprise Beans 3.2, as a part of Jakarta EE 8, and despite still using "EJB" abbreviation, this set of APIs has been officially renamed to "Jakarta Enterprise Beans" by the Eclipse Foundation so as not to tread on the Oracle "Java" trademark. EJB 3.2, final release (2013-05-28) JSR 345. Enterprise ...
The main role is to allow objects to access data and invoke methods on remote objects (objects residing in non-local memory space). Invoking a method on a remote object is known as remote method invocation (RMI) or remote invocation, and is the object-oriented programming analog of a remote procedure call (RPC).
This is because entity beans, in previous EJB specifications, called for much complicated code and imposed a heavy resource footprint, and they could be used only on Java EE application servers because of interconnections and dependencies in the source code between beans and DAO objects or persistence frameworks.
A name can be any string such as "com.example.ejb.MyBean". A name can also be an object that implements the Name interface; however, a string is the most common way to name an object. A name is bound to an object in the directory by storing either the object or a reference to the object in the directory service identified by the name.
However, it is possible to generate the IDL definitions for the involved RMI-IIOP data structures and use these definitions to exercise finer control between RMI-IIOP and CORBA communicating partners. Recent versions of RMI-IIOP derive their servants from the standard Servant class. Hence, it is possible to connect them to a CORBA ORB manually ...