Case C-143/16. Age discrimination

Is the rule of national law set out in Article 34 of Legislative Decree No 276 of 2003, according to which an on-call employment contract may, in any event, be concluded in respect of services provided by persons under 25 years of age, contrary to the principle of non-discrimination on grounds of age referred to in Directive 2000/78 1 and Article 21(1) of the Charter of Fundamental Rights of the European Union?