Java Data Objects

Name

Extent

Synopsis

An Extent is used to access all of the instances of a particular class and, optionally, its subclasses. An application can either iterate over all the instances or use the extent as the set of candidates instances filtered with a Query.

public interface Extent {
    public void                 close(Iterator it);
    public void                 closeAll(  );
    public Class                getCandidateClass(  );
    public PersistenceManager   getPersistenceManager(  );
    public boolean              hasSubclasses(  );
    public Iterator             iterator(  );
}

Returned by

PersistenceManager.getExtent( )

Passed to

PersistenceManager.newQuery( ), Query.setCandidates( )