isLoaded(entity, attributeName) - JPA PersistenceUtil's method

boolean isLoaded(
  Object entity,
  String attributeName

Determine the load state of a given persistent attribute.
entity - entity containing the attribute
attributeName - name of attribute whose load state is to be determined
false if entity's state has not been loaded or if the attribute state has not been loaded, else true
JPA 2.0

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.
ObjectDB is not an ORM JPA implementation but an Object Database for Java with built in JPA 2 support.