About JPA

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Manual
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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
42

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
Manual
42

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
JPA Doc
42

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
42

Defining a JPA Entity Class [2011-02-11]

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
Manual
42

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
41

JPA Reference (JavaDoc) [2018-08-18]

This reference contains the API documentation (similar to JavaDoc) of the Java Persistence API (JPA) 2.0. The content is derived from the original JPA documentation (in the EclipseLink JPA 2 RI) with some additions and notes. The four most basic JPA types are: All the other JPA types are organized
FAQ
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Which API should I use - JPA or JDO?

You can use ObjectDB with either the Java Persistence API (JPA) or the Java Data Objects (JDO) API. Both share similar architecture, design and abilities. When to prefer JPA JPA is more commonly used. Therefore, it might be the first choice for most new applications. You can use JPA as the primary
JPA Doc
41

JPA Reference (JavaDoc)

This reference contains the API documentation (similar to JavaDoc) of the Java Persistence API (JPA) 2.0. The content is derived from the original JPA documentation (in the EclipseLink JPA 2 RI) with some additions and notes. The four most basic JPA types are: All the other JPA types are organized
JPA Doc
41

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