Personalización avanzada > Services and Infrastructure Customization > Evolvable Classes > Examples of Generated Externalization Code for Evolvable Classes > Example of Generated Constants
  
Example of Generated Constants
static final long serialVersionUID = 1;
public static final long EXTERNALIZATION_VERSION_UID = 6676079877272797361L;
protected static final long OLD_FORMAT_VERSION_UID = -6779867937001963664L;
// OLD_FORMAT_VERSION_UID is only valid for R4 instances of the class