22 words

ManyToOne.optional - JPA annotation element

Annotation Element
javax.persistence.ManyToOne
boolean optional

(Optional) Whether the association is optional. If set to false then a non-null relationship must always exist.
Default value:
true
Since:
JPA 1.0

This documentation page is derived (with some adjustments) from the open source JPA 2 RI (EclipseLink)
and is available under the terms of the Eclipse Public License, v. 1.0 and Eclipse Distribution License, v. 1.0.
Object Relational Mapping (ORM) JPA 2 providers include Hibernate, EclipseLink, TopLink, OpenJPA and DataNucleus.
Object DB is not an ORM JPA implementation but an Object Database for Java with built in JPA 2 support.