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The term persistable types refers to data types that can be used for storing data in the database. ObjectDB supports all the JPA persistable types , which are: User defined classes - Entity classes, Mapped superclasses, Embeddable classes. Simple Java data types : Primitive types , Wrappers, String

classes) are represented in JPQL by the following types of expressions: Variables - FROM ... . But more often they are used in JPQL path expressions that navigate to values of simple types (number, boolean, string, date). Simple type values are more useful in queries. They have special operators

The following interfaces and enum represent types in the JPA Metamodel API:  See the Metamodel Type Interface Hierarchy section for more details and examples.

This section contains the most essential JPA types .

Jakarta Persistence (JPA) Interface jakarta.persistence.metamodel. Type Type Parameters: - The type of the represented object or attribute An instance of the type Type represents a persistent object or attribute type . Since: Jakarta Persistence (JPA) 2.0 Public Instance Methods Class getJavaType

Jakarta Persistence (JPA) Enum in jakarta.persistence.metamodel. Type jakarta.persistence.metamodel. Type .PersistenceType java.lang.Object ∟ java.lang.Enum ∟ jakarta.persistence.metamodel. Type ... (JPA) 1.0 Enum Constants BASIC Basic type Since: Jakarta Persistence (JPA) 1.0 EMBEDDABLE Embeddable

that Java reflection provides for general Java types . The Metamodel Interface The main interface of the JPA ... types  (which are referred to as managed types ) in the persistent object model. Three methods can be used to retrieve sets of types : // Get all the managed classes: // (entity classes

Jakarta Persistence (JPA) Method in jakarta.persistence.ColumnResult Class type (Optional) The Java type to which the column type is to be mapped. If the type element is not specified, the default JDBC type mapping for the column is used. Default: void/class Since: Jakarta Persistence (JPA) 2.1

Jakarta Persistence (JPA) Method in jakarta.persistence.metamodel. Type PersistenceType getPersistenceType() Return the persistence type . Returns: persistence type . Since: Jakarta Persistence (JPA) 1.0

Jakarta Persistence (JPA) Method in jakarta.persistence.metamodel. Type Class getJavaType() Return the represented Java type . Returns: Java type . Since: Jakarta Persistence (JPA) 1.0

Jakarta Persistence (JPA) Method in jakarta.persistence.criteria.Path Expression type () Create an expression corresponding to the type of the path. Returns: expression corresponding to the type of the path. Since: Jakarta Persistence (JPA) 1.0

Jakarta Persistence (JPA) Enum Constant in jakarta.persistence.metamodel.Bindable.BindableType ENTITY_ TYPE Entity type . See Also: EntityType Since: Jakarta Persistence (JPA) 1.0

Jakarta Persistence (JPA) Enum Constant in jakarta.persistence.metamodel. Type .PersistenceType BASIC Basic type Since: Jakarta Persistence (JPA) 1.0

Jakarta Persistence (JPA) Method in jakarta.persistence.NamedSubgraph Class type (Optional) The type represented by this subgraph. The element must be specified when this subgraph is extending a definition on behalf of a subclass. Default: void/class Since: Jakarta Persistence (JPA) 1.0

Jakarta Persistence (JPA) Method in jakarta.persistence.StoredProcedureParameter Class type JDBC type of the parameter. Since: Jakarta Persistence (JPA) 1.0

Jakarta Persistence (JPA) Method in jakarta.persistence.PersistenceContext PersistenceContextType type (Optional) Specifies whether a transaction-scoped persistence context or an extended persistence context is to be used. Default: PersistenceContextType.TRANSACTION Since: Jakarta Persistence (JPA) 1.0

Jakarta Persistence (JPA) Enum Constant in jakarta.persistence.metamodel. Type .PersistenceType ENTITY Entity class Since: Jakarta Persistence (JPA) 1.0

Jakarta Persistence (JPA) Enum Constant in jakarta.persistence.metamodel. Type .PersistenceType EMBEDDABLE Embeddable class Since: Jakarta Persistence (JPA) 1.0

Jakarta Persistence (JPA) Enum Constant in jakarta.persistence.metamodel. Type .PersistenceType MAPPED_SUPERCLASS Mapped superclass Since: Jakarta Persistence (JPA) 1.0

Jakarta Persistence (JPA) Constructor in jakarta.persistence.metamodel. Type .PersistenceType PersistenceType() Since: Jakarta Persistence (JPA) 1.0

name and either the same type or a convertible type , as explained below. A matching field ... the hierarchy, removing an intermediate class in the hierarchy, etc.). Convertible Types When an old matching field is found but its type is different than the type of the new field (with the same name

 and type versioning. Class hierarchy changes are handled automatically. New added fields are handled automatically. Removed fields are handled automatically. Most field type changes are handled ... types , fields and properties . Object Model & Data Types ObjectDB supports persisting complex Java

Literals in JPQL, as in Java, represent constant values. JPQL supports various types of literals ... (e.g. 'abc' ), enum literals (e.g. mypackage.MyEnum.MY_VALUE ) and entity type literals (e.g. Country ... the ordinary Java syntax for enum values, but the fully qualified name of the enum type

Jakarta Persistence (JPA) Interface jakarta.persistence.metamodel.EntityType Type Parameters: - The represented entity type . Super Interfaces: IdentifiableType , Bindable , ManagedType , Type An instance of EntityType represents an entity type . Since: Jakarta Persistence (JPA) 2.0 Public Instance

Jakarta Persistence (JPA) Interface jakarta.persistence.metamodel.IdentifiableType Type Parameters: - The represented entity or mapped superclass type . Super Interfaces: ManagedType , Type An instance of the type IdentifiableType represents an entity or mapped superclass type . Since: Jakarta

Jakarta Persistence (JPA) Interface jakarta.persistence.metamodel.MappedSuperclassType Type Parameters: - The represented mapped superclass type Super Interfaces: IdentifiableType , ManagedType , Type An instance of the type MappedSuperclassType represents a mapped superclass type . Since: Jakarta

persistable types . ObjectDB supports persistent fields with any declared static type , including a generic java.lang.Object , as long as the type of the actual value at runtime is persistable (or null ... - for references of entity types . OneToMany , ManyToMany - for collections and maps of entity types

Jakarta Persistence (JPA) Interface jakarta.persistence.metamodel.ManagedType Type Parameters: - The represented type . Super Interfaces: Type Instances of the type ManagedType represent entity, mapped superclass, and embeddable types . Since: Jakarta Persistence (JPA) 2.0 Public Instance Methods

Jakarta Persistence (JPA) Interface jakarta.persistence.metamodel.EmbeddableType Type Parameters: - The represented embeddable type . Super Interfaces: ManagedType , Type An instance of EmbeddableType represents an embeddable type . Since: Jakarta Persistence (JPA) 2.0 Public Instance Methods

and JDO. JPA follows Java numeric promotion principles. For example, the resulting type ... to 10.7 The ABS function takes as an argument a numeric value of any type and returns a value of the same type . The MOD Function The MOD function calculates the remainder of the division of one number by

of bookmarked entity objects. The [Schema] window shows the user defined persistable types (entity ... Windows The Explorer provides two types of viewer windows for viewing the database data. The Table ... of a single field in a single database object. This type of viewer is useful for viewing data

Jakarta Persistence (JPA) Interface jakarta.persistence.EntityGraph Type Parameters: - The type of the root entity. Super Interfaces: Graph This type represents the root of an entity graph ... and entity relationships. The root must be an entity type . The methods to add subgraphs implicitly create

Types Comparison is supported for values of the following data types : Values of numeric types , including primitive types ( byte , short , char , int , long , float , double ), wrapper types ( Byte ... , comparing the content rather than the identity. Values of the boolean and Boolean types can be compared by

Jakarta Persistence (JPA) Interface jakarta.persistence.Subgraph Type Parameters: - The type of the attribute. Super Interfaces: Graph This type represents a subgraph for an attribute node that corresponds to a managed type . Using this class, an entity subgraph can be embedded

. IllegalArgumentException - if the attribute is not an attribute of this managed type .. Since: Jakarta Persistence ... to a collection element that is a managed type . This allows for construction of multi-node entity graphs that include related managed types . Parameters: attribute - attribute Returns: subgraph for the element

(defined by an entity type and primary key) there is at most one entity instance. The entity instances ... their primary key, and execute queries which range over entity types . An entity may be disassociated from ... pessimistic lock on an entity instance. The full range of possible lock types is enumerated by LockModeType

appearing in the query string. The parameter type is inferred by the context. In the above example, a comparison of :name to a field whose type is String indicates that the type of :name itself is String ... (of type ParameterExpression or its super interface Parameter ) rather than by names or numbers

the database is uniquely identified (and can be retrieved from the database) by the combination of its type ... . Instances of other persistable types are always stored as part of their containing entity objects ... that is set by the application can have one of the following types : Primitive types : boolean , byte , short

Jakarta Persistence (JPA) Interface jakarta.persistence.criteria.MapJoin Type Parameters: - the source type of the join - the type of the target Map value - the type of the target Map key Super ... The MapJoin interface is the type of the result of joining to a collection over an association or element

Jakarta Persistence (JPA) Interface jakarta.persistence.criteria.PluralJoin Type Parameters: - the source type - the element type of the collection - the collection type Super Interfaces: Join ... functionality that is common to joins to all collection types . It is not intended to be used directly in

Jakarta Persistence (JPA) Interface jakarta.persistence.criteria.SetJoin Type Parameters: - the source type of the join - the element type of the target Set Super Interfaces: PluralJoin , Join , From , Path , FetchParent , Expression , Selection , TupleElement The SetJoin interface is the type

Jakarta Persistence (JPA) Interface jakarta.persistence.criteria.CollectionJoin Type Parameters: - the source type of the join - the element type of the target Collection Super Interfaces ... interface is the type of the result of joining to a collection over an association or element collection

Jakarta Persistence (JPA) Interface jakarta.persistence.criteria.ListJoin Type Parameters: - the source type of the join - the element type of the target List Super Interfaces: PluralJoin , Join , From , Path , FetchParent , Expression , Selection , TupleElement The ListJoin interface is the type

Jakarta Persistence (JPA) Interface jakarta.persistence.criteria.Join Type Parameters: - the source type of the join - the target type of the join Super Interfaces: From , Path , FetchParent , Expression , Selection , TupleElement A join to an entity, embeddable, or basic type . Since: Jakarta

Jakarta Persistence (JPA) Interface jakarta.persistence.criteria.From Type Parameters: - the source type - the target type Super Interfaces: Path , FetchParent , Expression , Selection , TupleElement Represents a bound type , usually an entity that appears in the from clause

objects (e.g. values of system types and user defined embeddable objects) return as results value ... ); The select method takes one argument of type Selection  and sets it as the SELECT clause content  ... above. The behavior of the multiselect  method depends on the query result type (as set

at the FROM clause level. JPA 2, however, adds support for filtering instances of specific types at the WHERE clause level by using a type expression . For example, in the following query, c iterates ... variables represent iteration over all the database objects of a specified entity type . JPQL provides

should be used mainly when the query result type is unknown or when a query returns polymorphic ... . When a more specific result type is expected queries should usually use the TypedQuery interface. It is easier to run queries and process the query results in a type safe manner when using the TypedQuery interface

, but the version of Query returns a result list of a raw type (non generic) instead of a parameterized (generic) type : Query query = em. createQuery ("SELECT c FROM Country c"); List results = query. getResultList (); An attempt to cast the above results to a parameterized type ( List ) will cause a compilation

Jakarta Persistence (JPA) Interface jakarta.persistence.criteria.Root Type Parameters: - the entity type referenced by the root Super Interfaces: From , Path , FetchParent , Expression , Selection , TupleElement A root type in the from clause. Query roots always reference entities. Since: Jakarta