If we have a prototype and want to find out if there is an object in the database with the same field values, we can simply use QBE:
01private static void retrieveEqual() { 02
ObjectContainer container = database(); 03
if (container != null) { 04
try { 05
ObjectSet result = container.get(new Pilot("Kimi Raikkonnen", 100)); 06
if (result.size() > 0){ 07
System.out.println("Found equal object: " + result.next().toString()); 08
} else { 09
System.out.println("No equal object exist in the database"); 10
} 11
} catch (Exception ex) { 12
System.out.println("System Exception: " + ex.getMessage()); 13
} finally { 14
closeDatabase(); 15
} 16
} 17
}
This method allows to combine retrieval and comparing in one operation.