unwrap(cls) - JPA Query's method
Method
javax.persistence.Query
T unwrap(
Class<T> cls
)
Return an object of the specified type to allow access to the provider-specific API. If the provider's query implementation does not support the specified class, the
PersistenceException is thrown.
- Parameters:
-
cls- the class of the object to be returned. This is normally either the underlying query implementation class or an interface that it implements.
- Returns:
- an instance of the specified class
- Throws:
-
PersistenceException- if the provider does not support the call
- Since:
- 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.
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.
