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*/
package org.bedework.calfacade.base;
/** Interface which defines an implementing class as being differeable.
*
* This is to distinguish it from Comparable. The issue here is that hibernate
* requires that equals return true for entities which refer to the same db
* object. Thus objects with the same key values will return equals == true
* even if other fields differ.
*
*
The Comparable interface declaration states
*
It is strongly recommended (though not required) that natural orderings
* be consistent with equals.
*
* This means we need some other way to determine that two entities, though
* equal are in fact different in some respect. For example, we may have two
* attendee objects for the same person but with a different partstat.
*
* @author Mike Douglass
* @version 1.0
*
* @param
*/
public interface Differable {
/** Return true if the entity differs in any way.
*
* @param val
* @return boolean
*/
public boolean differsFrom(T val);
}