oracle.toplink.essentials.descriptors.ClassExtractor Maven / Gradle / Ivy
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package oracle.toplink.essentials.descriptors;
import oracle.toplink.essentials.exceptions.*;
import oracle.toplink.essentials.sessions.*;
import oracle.toplink.essentials.descriptors.ClassDescriptor;
/**
* Purpose:
* Abstract class to allow complex inheritance support. Typically class indicators are used to define inheritance in the database,
* however in complex cases the class type may be determined through another mechanism.
* The class extractor must be able to determine and return the class type from the database row.
*
* @see oracle.toplink.essentials.descriptors.InheritancePolicy#setClassExtractor(ClassExtrator)
*/
public abstract class ClassExtractor {
/**
* Extract/compute the class from the database row and return the class.
* Map is used as the public interface to database row, the key is the field name,
* the value is the database value.
*/
public abstract Class extractClassFromRow(Record databaseRow, Session session);
/**
* Allow for any initialization.
*/
public void initialize(ClassDescriptor descriptor, Session session) throws DescriptorException {
// Do nothing by default.
}
}