The Query API in JPA (EJB 3.0)

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Introduction One of the disadvantage of locating the entity objects using the EntityManager.find() and EntityManager.getReference() methods is, we cannot specify any powerful search criteria for searching the entity objects. All we can provide is the primary key to request for a particular object. Another fact is the class name of entity must be known. The […]

Introduction to Java Persistence API(JPA)

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Introduction Java Persistence API (JPA) provides POJO (Plain Old Java Object) standard and object relational mapping (OR mapping) for data persistence among applications. Persistence, which deals with storing and retrieving of application data, can now be programmed with Java Persistence API starting from EJB 3.0 as a result of JSR 220. This API has borrowed […]

EJB 3.0 Timer Services

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Starting from EJB 2.1, Timer Services are available for building J2EE Applications that depends on time based services. Time based services are mostly used in scheduling applications. Technically, these scheduling applications are called workflows. also read: Java EE Tutorials EJB Interview Questions EJB 3 Web Services Annotation and Dependency Injection in EJB 3 Query API […]