ObjectDB Database Search

JPA Method in jakarta.persistence.metamodel.Metamodel EntityType entity (   String entityName ) Return the metamodel entity type representing the entity . Parameters: entityName - the name of the represented entity Return: the metamodel entity type Throws: IllegalArgumentException

  entity ) Create and add a query root corresponding to the entity that is the target of the update. A CriteriaUpdate object has a single root, the entity that is being updated. Parameters: entity - metamodel entity representing the entity of type X Return: query root corresponding to the given entity Since: JPA 2.1

JPA Method in jakarta.persistence.metamodel.Metamodel EntityType entity (   Class  cls ) Return the metamodel entity type representing the entity . Parameters: cls - the type of the represented entity Return: the metamodel entity type Throws: IllegalArgumentException - if not an entity Since: JPA 2.0

; entity ) Determine the load state of an entity . This method can be used to determine the load state of an entity passed as a reference. An entity is considered loaded if all attributes for which FetchType ... : entity - whose load state is to be determined Return: false if the entity has not been loaded, else true Since: JPA 2.0

JPA Method in jakarta.persistence.EntityManager boolean contains (   Object  entity ) Determine if the given object is a managed entity instance belonging to the current persistence context. Parameters: entity - entity instance Return: boolean value indicating if entity belongs

; entity ) Create and add a query root corresponding to the given entity , forming a cartesian product with any existing roots. Parameters: entity - metamodel entity representing the entity of type X Return: query root corresponding to the given entity Since: JPA 2.0

; entity ) Get the current plain held by this persistence context on the given managed entity instance. Parameters: entity - a managed entity instance Return: the lock mode currently held Throws: TransactionRequiredException - if there is no active transaction or if the entity manager has not

;Object  entity ,    String attributeName ) If the provider determines that the entity has been provided by itself and that the state of the specified attribute has been loaded, this method returns LoadState.LOADED . If a provider determines that the entity has been provided by

; entity ,    String attributeName ) Determine the load state of a given persistent attribute of an entity belonging to the persistence unit. Parameters: entity - entity instance ... : false if entity's state has not been loaded or if the attribute state has not been loaded, else true Since: JPA 2.0

JPA Method in jakarta.persistence.PersistenceUnitUtil boolean isLoaded (   E  entity ... attribute of an entity belonging to the persistence unit. Parameters: entity - entity instance containing the attribute attribute - attribute whose load state is to be determined Return: false if entity's

JPA Constructor in jakarta.persistence.PessimisticLockException PessimisticLockException (   Object  entity ) Constructs a new PessimisticLockException exception with the specified entity . Parameters: entity - the entity . Since: JPA 2.0

;String message,    Throwable cause,    Object  entity ) Constructs a new LockTimeoutException exception with the specified detail message, cause, and entity . Parameters: message - the detail message. cause - the cause. entity - the entity . Since: JPA 2.0

; entity ,    String attributeName ) Determine the load state of a given persistent attribute. Parameters: entity - entity containing the attribute attributeName - name of attribute whose load state is to be determined Return: false if entity's state has not been loaded or

JPA Constructor in jakarta.persistence.OptimisticLockException OptimisticLockException (   String message,    Throwable cause,    Object  entity ... , and entity . Parameters: message - the detail message. cause - the cause. entity - the entity . Since: JPA 1.0

JPA Constructor in jakarta.persistence.OptimisticLockException OptimisticLockException (   Object  entity ) Constructs a new OptimisticLockException exception with the specified entity . Parameters: entity - the entity . Since: JPA 1.0

JPA Method in jakarta.persistence.criteria.From Join join (    EntityType   entity ,     JoinType  joinType ) Create and add a join to the given entity . Parameters: entity - metamodel entity representing the join target joinType - join type Return: the resulting join Since: JPA 3.2

JPA Method in jakarta.persistence.criteria.From Join join (    EntityType   entity ) Create and add an inner join to the given entity . Parameters: entity - metamodel entity representing the join target Return: the resulting join Since: JPA 3.2

JPA Annotation Attribute in jakarta.persistence. Entity String name default "" (Optional) The entity name. Defaults to the unqualified name of the entity class. This name is used to refer to the entity in queries. The name must not be a reserved literal in the Jakarta Persistence query language. Since: JPA 1.0

; entity ) Constructs a new PessimisticLockException exception with the specified detail message, cause, and entity . Parameters: message - the detail message. cause - the cause. entity - the entity . Since: JPA 2.0

JPA Constructor in jakarta.persistence.LockTimeoutException LockTimeoutException (   Object  entity ) Constructs a new LockTimeoutException exception with the specified object. Parameters: entity - the entity . Since: JPA 2.0

JPA Enum Constant in javax.persistence.metamodel.Bindable $BindableType ENTITY _TYPE Entity type Since: JPA 2.0

JPA Annotation Attribute in jakarta.persistence.NamedNativeQuery EntityResult [] entities default {} Specifies the result set mapping to entities . May not be used in combination with resultSetMapping . Since: JPA 3.2

JPA Annotation Attribute in jakarta.persistence.SqlResultSetMapping EntityResult [] entities default {} Specifies the result set mapping to entities . Since: JPA 1.0

JPA Enum Constant in javax.persistence.metamodel.Type $PersistenceType ENTITY Entity Since: JPA 2.0

Modifications to entity classes that do not change their persistent field definitions ... of an entity class are detected by ObjectDB. New entity objects have to be stored in the new class schema, and old entity objects, which were stored previously in the old class schema

Instances of user defined persistable classes ( entity classes, mapped super classes and embeddable ... and values. For example - c.capital , where c represents a Country entity object uses the capital persistent field in the Country class to navigate to the associated Capital entity object. Path expression

, if they happen, are detected earlier. Optimistic Locking ObjectDB maintains a version number for every entity object. The initial version of a new entity object (when it is stored in the database for the first time) is 1. In every transaction in which an entity object is modified its version number

of this document. "Licensor" shall mean the copyright owner or entity authorized by the copyright owner that is granting the License. "Legal Entity " shall mean the union of the acting entity and all other entities that control, are controlled by, or are under common control with that entity

(e.g. 'abc' ), enum literals (e.g. mypackage.MyEnum.MY_VALUE ) and entity type literals (e.g. Country ... { RED, GREEN, BLUE } Then example.ui.Color.RED is a valid literal in JPQL, but Color.RED is not. Entity Type Literals Entity type literals represent entity types in JPQL, similar to the way that java

Existing entity objects can be updated, as explained in chapter 2 , by: Retrieving the entity objects into an EntityManager . Updating the relevant entity object fields  ... provide an alternative way of updating entity objects. Unlike SELECT queries, which are used

for entity objects with no primary key fields defined (as explained in the previous section ). The same ... @GeneratedValue with the AUTO strategy: @ Entity public class EntityWithAutoId1 { @Id @GeneratedValue ... definition is equivalent: @ Entity public class EntityWithAutoId2 { @Id @GeneratedValue long id

to exactly one  entity class or mapped superclass - usually to the most relevant entity class ... carefully to avoid collision (e.g. by using the unique entity name as a prefix). It makes sense to add the above  @NamedQuery to the Country entity class: @ Entity @NamedQuery ( name ="Country.findAll

As explained in chapter 2 , entity objects can be deleted from the database by: Retrieving the entity objects into an EntityManager . Removing these objects from the EntityManager   ... DELETE queries provide an alternative way for deleting entity objects. Unlike SELECT queries

. Three methods can be used to retrieve sets of types: // Get all the managed classes: // ( entity classes ... (); // Get all the entity classes: Set allEntityTypes = metamodel. getEntities (); // Get all the embeddable ... methods can be used to retrieve a specific type by its Class instance: // Get a managed type ( entity

). Up to 2,147,483,648 entity classes per database file. Up to 2,147,483,648 indices per database file. Up to 9,223,372,036,854,775,808 entity objects per database file. Unlimited database connections ... . Configurable - minimum/maximum connections and timeout. Caching L1 entity object cache

are query identification variables that iterate over all the database objects of a specific entity class hierarchy (i.e. an entity class and all its descendant entity classes). Identification variables ... of an entity class in a JPQL query is the unqualified name of the class (e.g. just Country with no package

classes and objects. For example, a JPQL query can retrieve and return entity objects ... elements such as names of entity classes and persistent fields, which are case sensitive. In addition ... over objects in the database. A query variable that is bound to an entity class is referred to as a range

( entity classes , embeddable classes and mapped superclasses ), and is usually optional ... efficient tracking of persistent field modifications, avoiding the need for snapshot comparison of entities ... loading of entity objects. With no enhancement, only persistent collection and map fields

entity that distributes the Program. "Licensed Patents" mean patent claims licensable by ... property rights of any other entity . Each Contributor disclaims any liability to Recipient for claims brought by any other entity based on infringement of intellectual property rights or otherwise. As

. Whenever possible: Use a single Java file with one main class + static inner classes for entity ... ();     }     @ Entity     public static class MyEntity ... warnings (There is no ID defined for this entity hierarchy, The class should have a no-arg public or

because of an attempt to store a new entity object with a primary key that is already in use by another existing entity object, the nested exception is: Other common causes for RollbackException are lock failures: Exceptions can also be thrown on an attempt to retrieve entity objects from the database. For example

some ORM JPA providers) is defined in the entity class or not. It can be disabled by setting the  ... indexes are handled. When a new index is defined for an existing entity class that already has instances ... Removing ObjectDB evaluation restrictions (of 10 entity classes and 1,000,000 entity objects

, and is only able to manage persistence of entities belonging to the associated persistence unit ... . {@snippet : // inject the container-managed entity manager @PersistenceContext(unitName="orderMgt" ... with a distinct persistence context . A persistence context is a set of entity instances in which for any

automatic optimistic locking to prevent concurrent changes to entity objects by multiple users. JPA 2 ... " . When LAZY is used result entity objects are returned as references (with no content). This could be useful when the shared L2 cache is enabled and entity objects may already be available in the cache

it to store, retrieve, update and delete database objects. Storing New Entity Objects The following ... (); for (int i = 0; i = 100) { em. remove (p); // delete entity } else { p.setX(p.getX() + 100); // update entity } } em. getTransaction (). commit (); In the above example all the Point objects whose x

that has signed the guestbook is represented by a  Guest JPA entity object and all the  Guest entity objects are stored in an ObjectDB database. Required Software For this tutorial you will need

that has signed the guestbook is represented as Guest JPA entity object, and all Guest entity objects

the next tutorial step) - a new Guest entity object is constructed and stored in the database. All the Guest entity objects are retrieved from the database and stored in the request's "guest" attribute

The Guest entity objects will be stored in an ObjectDB database, which will be represented by a JPA's EntityManagerFactory instance with a global application scope. We have to register ... the Enhancer to enhance the entity class, creates an EntityManagerFactory instance and stores

. Every visitor that has signed the guestbook is represented by a Guest entity object and all the Guest entity objects are stored in an ObjectDB database. Required Software For this tutorial