public class StringPrefixedSequenceIdGenerator extends SequenceStyleGenerator {

public static final String VALUE_PREFIX_PARAMETER = "valuePrefix";
public static final String VALUE_PREFIX_DEFAULT = "";
private String valuePrefix;

public static final String NUMBER_FORMAT_PARAMETER = "numberFormat";
public static final String NUMBER_FORMAT_DEFAULT = "%d";
private String numberFormat;

@Override
public Serializable generate(SharedSessionContractImplementor session,
        Object object) throws HibernateException {
    return valuePrefix + String.format(numberFormat, super.generate(session, object));
}

@Override
public void configure(Type type, Properties params,
        ServiceRegistry serviceRegistry) throws MappingException {
    super.configure(LongType.INSTANCE, params, serviceRegistry);
    valuePrefix = ConfigurationHelper.getString(VALUE_PREFIX_PARAMETER,
            params, VALUE_PREFIX_DEFAULT);
    numberFormat = ConfigurationHelper.getString(NUMBER_FORMAT_PARAMETER,
            params, NUMBER_FORMAT_DEFAULT);
}
}