oracle.toplink.essentials.internal.indirection.BackupValueHolder Maven / Gradle / Ivy
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package oracle.toplink.essentials.internal.indirection;
import oracle.toplink.essentials.indirection.*;
/**
* Used as the backup value holder in the unit of work for transparent indirection.
* This ensure that a reference to the original value holder is held in case the
* transparent collection or proxy is replace without first instantiating the original.
*
* @since 10.1.3
* @author James Sutherland
*/
public class BackupValueHolder extends ValueHolder {
/** Stores the original uow clone's value holder. */
protected ValueHolderInterface unitOfWorkValueHolder;
public BackupValueHolder(ValueHolderInterface unitOfWorkValueHolder) {
this.unitOfWorkValueHolder = unitOfWorkValueHolder;
}
/**
* If the original value holder was not instantiated,
* then first instantiate it to obtain the backup value.
*/
public Object getValue() {
// Ensures instantiation of the original, and setting of this back value holder's value.
getUnitOfWorkValueHolder().getValue();
return value;
}
/**
* Return the original uow clone's value holder.
*/
public ValueHolderInterface getUnitOfWorkValueHolder() {
return unitOfWorkValueHolder;
}
}