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Manual
45

JPA Entity Fields

either the Java transient modifier (which also affects serialization) or the JPA @Transient annotation ... and maps of entity types. Basic - for any other persistable type. In JPA only Basic is optional ... of these annotations, so they are useful only for classes that are also in use with an ORM JPA
Result
45

ObjectDB - Object Database for Java (JPA/JDO)

for developing Java database applications using the Java Persistence API (JPA). It is the first persistence solution that combined a powerful database with JPA support in one product, saving the need to integrate an external JPA ORM with a database. ObjectDB is an extremely easy to use pure Java Object
Manual
45

CRUD Database Operations with JPA

Given an EntityManager, em, that represents a JPA connection to the object database, we can use ... persisting objects in the database in more detail. JPA Queries with JPQL We can get the number of Point ... COUNT(p) FROM Point p") instructs JPA to count all the Point objects in the database. If you have used
Manual
44

JPA Persistable Types

. ObjectDB supports all the JPA persistable types, which are: User defined classes - Entity classes ... ; @Entity public class MyEntity { } Entity Class Requirements A portable JPA entity class ... Superclasses In JPA, classes that are declared as mapped superclasses have some of the features of entity
JPA Doc
44

JPA 2 Annotations

JPA defines dozens of annotations that can be divided into the following groups: Annotations for JPA aware classes: Annotations for fields in JPA persistable classes: Annotations for additional JPA configuration: Annotations for JPA lifecycle event callbacks: Java EE container annotations: Many
Manual
44

Setting and Tuning of JPA Queries

of other EntityManager instances). JPA implementations can easily make uncommitted changes visible in simple JPA operations, such as find. However, query execution is much more complex ... order to be visible to the query. Flush policy in JPA is represented by the FlushModeType enum
Manual
44

Defining a JPA Entity Class

To be able to store Point objects in the database using JPA we need to define an entity class. A JPA entity class is a POJO (Plain Old Java Object) class, i.e. an ordinary Java class that is marked ... JPA addition is the @Entity annotation, which marks the class as an entity class. An attempt
JPA Doc
43

JPA Metamodel API

The JPA Metamodel API, which is introduced in JPA 2.0, enables examining the classes, fields ... of the JPA Metamodel API is: Types (mainly classes) and attributes (persistent field and properties ... : The JPA Metamodel API may optionally be used with the JPA Criteria API. Many of the interfaces in
Manual
43

Query Parameters in JPA

(:) followed by a valid JPQL identifier that serves as the parameter name. JPA does not provide an API ... . Criteria Query Parameters In a JPA query that is built by using the JPA Criteria API - parameters ... of which are overridden in TypedQuery. That large number of methods is not typical to JPA, which generally
Manual
42

JPA Named Queries

can be defined in JPA XML mapping files instead of using the @NamedQuery annotation. ObjectDB supports JPA XML ... mainly for Object Relational Mapping (ORM) JPA providers and less so when using ObjectDB ... ("SELECT c FROM Country c"); List results = query.getResultList(); One of the reasons that JPA requires