code: public Object sqlToJava(Object source)
      {
          if(source == null)
              return null;
          try
          {
              return SerializationUtils.deserialize((byte[]) source);
          }
          catch(Throwable t)
          {
              throw new ConversionException(t);
          }
      }
docs: /*
  @see FieldConversion#sqlToJava(Object)