BaseIdentifierGenerator.java

/**
* A custom Id generator based on combination of long time hex string and UUID
*
* @author Ehab Qadah
*/
public class BaseIdentifierGenerator extends UUIDGenerator {

private static final int NUMBER_OF_CHARS_IN_ID_PART = -5;

@Override
public Serializable generate(SharedSessionContractImplementor session, Object obj) throws HibernateException {
    // Generate a custom ID for the new entity
    final String uuid = super.generate(session, obj).toString();

    final long longTimeRandom = System.nanoTime() + System.currentTimeMillis() 
    + new Random().nextLong() + Objects.hash(obj);

    final String timeHex = Long.toHexString(longTimeRandom);
    return StringUtils.substring(timeHex, NUMBER_OF_CHARS_IN_ID_PART) 
    + StringUtils.substring(uuid, NUMBER_OF_CHARS_IN_ID_PART);
}
}