About types

JPA Persistable Types

Explains how JPA manages types, including entity classes, embeddable classes, primitive types, wrappers, string, date, enum, collections and maps. The term persistable types refers to data types that can be used in storing data in the database. ObjectDB supports all the JPA persistable types, which are: User defined classes - Entity classes, Mapped ...

JPA Metamodel API

Explains how to use the JPA Metamodel API to retrieve details on the types and attributes of the persistent object model.... the ability that Java reflection provides for general Java types. This page covers the following topics: The ... several methods for exploring user defined persistable types (which are referred to as managed types) in the persistent ...

Paths and Types in JPQL and Criteria API

Explains how to use object expressions (path navigation, type) in JPA/JPQL.... classes) are represented in JPQL by the following types of expressions: Variables - FROM identification ... in JPQL path expressions that navigate to values of simple types (number, boolean, string, date). Simple type values are more ...

javax.persistence.metamodel.EntityType

Instances of the type EntityType represent entity types.(Interface of JPA)

javax.persistence.metamodel.MappedSuperclassType

Instances of the type MappedSuperclassType represent mapped superclass types.(Interface of JPA)

javax.persistence.metamodel.IdentifiableType

Instances of the type IdentifiableType represent entity or mapped superclass types.(Interface of JPA)

javax.persistence.metamodel.ManagedType

Instances of the type ManagedType represent entity, mapped superclass, and embeddable types.(Interface of JPA)

javax.persistence.metamodel.EmbeddableType

Instances of the type EmbeddableType represent embeddable types.(Interface of JPA)

type()

Create an expression corresponding to the type of the path.(Method of javax.persistence.criteria.Path)

Literals in JPQL and Criteria Queries

Describes literals in JPQL, including null, false, true, numbers, strings, dates enums and types.... in Java, represent constant values. JPQL supports various types of literals including NULL , boolean literals ( TRUE and FALSE ... Literals Entity type literals represent entity types in JPQL, similar to the way that java.lang.Class instances in Java ...