 92 | To store objects in an ObjectDB database using JPA we need to define an entity class: Open the [New ... : package tutorial;
import java.io.Serializable;
import javax.persistence.*;
@Entity
public ... should represent Point objects in the database. Besides the @Entity annotation and the id field |
92 | To store objects in an ObjectDB database using JPA we need to define an entity class: Open the [New ... : package tutorial;
import java.io.Serializable;
import javax.persistence.*;
@Entity
public ... should represent Point objects in the database. Besides the @Entity annotation and the id field |
91 | JPA Entity classes are user defined classes whose instances can be stored in a database. To store data in an ObjectDB database using JPA you have to define entity classes that represent your application data object model. This chapter explains how to define and use entity classes. |
30 | . ObjectDB supports all the JPA persistable types, which are: User defined classes - Entity classes ... and Serializable types (user or system defined). Note: Only instances of entity classes can be stored in the database directly. Other persistable types can be embedded in entity classes as fields. In |
30 | Callback methods are user defined methods that are attached to entity lifecycle events ... methods are methods that are defined within an entity class. For example, the following entity class defines all the supported callback methods with empty implementations:
@Entity
public static class |
30 | The ObjectDB configuration file contains one root element with seven subelements:
...
...
<entities> ... entities>
...
...
...
... |
30 | is represented by a Guest JPA entity object and all the Guest entity objects are stored in an ObjectDB |
30 | is represented by a Guest JPA entity object and all the Guest entity objects are stored in an ObjectDB |
29 | Method javax.persistence.EntityManager void detach( Object entity ) Remove the given entity from the persistence context, causing a managed entity to become detached. Unflushed changes made to the entity if any (including removal of the entity), will not be synchronized to the database. Entities |
29 | Method javax.persistence.EntityManager void lock( Object entity, LockModeType lockMode ) Lock an entity instance that is contained in the persistence context with the specified lock mode type. If a pessimistic lock mode type is specified and the entity contains a version attribute |