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getIdentifier(entity) - JPA PersistenceUnitUtil's method

Return the id of the entity. A generated id is not guaranteed to be available until after the database insert has occurred. Returns null if the entity does not yet have an id.
Parameters:
entity - entity instance
Returns:
id of the entity
Throws:
IllegalArgumentException - if the object is found not to be an entity
Since:
JPA 2.0
< PersistenceUnitUtil^ PersistenceUnitUtilCache >
 
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