cast an object to an interface in java?

Question

if we cast an object to an interface, won\'t this object be able to call its own methods? in the following example, myObj will only be able to call MyInterface meth

Answer 1

A simple analogy:

Consider a Chef(Interface). And there are Chinese chef(classes) and American chef(classes). Now, there is a Hotel looking out to recruit a chef based on some eligibility criteria such as

• can cook Non-vegeterian
• can cook vegeterian
• have experience of 5 years

Here, the eligibility is the context within which the Chef type person is evaluated(Types functionality). Now, there may be cases where Chinese chef can also cook sea food , Italian dishes etc. so could be the case with American counterpart. All these may seem irrelevant to Hotel manager as he is only concerned with required criteria.

Chefs work in a hotel is analogous to Chef type object utilised in code. The obvious work would be to cook vegeterian and non-vegeterian food(criteria or interface methods). That does not mean that the Hotel cannot utilize the Chinese chef's sea food making skills.

It's just a matter of specifying what skills(functionality) the Hotel is looking for.

Hope you get the idea.