Eclipse framework provides two interfaces: stable interfaces (APIs) and unstable interfaces (non-APIs). Despite the non-APIs being discouraged and unsupported, their usage is not uncommon. Previous studies showed that applications using relatively old non-APIs are more likely to be compatible with new releases compared to the ones that used newly introduced non-APIs; that the growth rate of non-APIs is nearly twice as much as that of APIs; and that the promotion of non-API to APIs happens at a slow pace since API …