Download
Forum
Login
My Account
Admin
A
Logout
Fast Object Database for Java - with JPA/JDO support
Object
DB
Object
DB
ObjectDB
Overview
Features
Download
Change Log
License
Company
Tutorials
Quick Start with JPA
JPA Web App (Tomcat)
Java EE JPA (GlassFish)
Spring MVC and JPA
Manual
Quick Tour
Entity Classes
Using JPA
JPA Queries
Tools and Utilities
Configuration
JPA
Persistence
EntityManagerFactory
EntityManager
EntityTransaction
Annotations
Queries
Metamodel
Miscellaneous
Exceptions
JDO
JDOHelper
PersistenceManagerFactory
PersistenceManager
Transaction
Query
Extent
Annotations
Callbacks
Listeners
Predefined ID Classes
Miscellaneous
Exceptions
Support
FAQ
Forum
Issue Tracking
Help Desk
Manager
Home
»
JPA
»
Annotations
»
Field Modifiers
»
Basic
»
Basic.optional - JPA annotation element
JPA Reference
Persistence
EntityManagerFactory
EntityManager
EntityTransaction
Annotations
Class Modifiers
Field Modifiers
Basic
Embedded
ElementCollection
Id
EmbeddedId
Version
Transient
Enumerated
MapKeyEnumerated
EnumType
Temporal
TemporalType
MapKeyTemporal
Relationships
Access Modes
Value Generation
Callback Methods
JPQL Queries
Java EE
Mapping (ORM)
SQL Queries
Queries
Metamodel
Miscellaneous
Exceptions
Basic.optional - JPA annotation element
Annotation Element
javax.persistence.Basic
boolean optional
(Optional) Defines whether the value of the field or property may be null. This is a hint and is disregarded for primitive types; it may be used in schema generation. If not specified, defaults to
true
.
Default value:
true
Since:
JPA 1.0
< Basic
^ Basic
Embedded >