Private members are only accessible within the class defining them. Protected members are accessible in the class that defines them and in classes that inherit from that class. Edit: Both are also accessible by friends of their class, and in the case of protected members, by friends of their derived classes. Edit 2: Use whatever … Read more
The inner class is just a way to cleanly separate some functionality that really belongs to the original outer class. They are intended to be used when you have 2 requirements: Some piece of functionality in your outer class would be most clear if it was implemented in a separate class. Even though it’s in … Read more
what are Access Specifiers? There are 3 access specifiers for a class/struct/Union in C++. These access specifiers define how the members of the class can be accessed. Of course, any member of a class is accessible within that class(Inside any member function of that same class). Moving ahead to type of access specifiers, they are: … Read more
If you want to unit test a private method, something may be wrong. Unit tests are (generally speaking) meant to test the interface of a class, meaning its public (and protected) methods. You can of course “hack” a solution to this (even if just by making the methods public), but you may also want to … Read more
Most of the confusion in the question/answers here surrounds the definition of Inheritance. Obviously, as @DigitalRoss explains an OBJECT of a subclass must contain its superclass’s private fields. As he states, having no access to a private member doesn’t mean its not there. However. This is different than the notion of inheritance for a class. … Read more
It’s cultural. In Python, you don’t write to other classes’ instance or class variables. In Java, nothing prevents you from doing the same if you really want to – after all, you can always edit the source of the class itself to achieve the same effect. Python drops that pretence of security and encourages programmers … Read more
In order to access private fields, you need to get them from the class’s declared fields and then make them accessible: Field f = obj.getClass().getDeclaredField(“stuffIWant”); //NoSuchFieldException f.setAccessible(true); Hashtable iWantThis = (Hashtable) f.get(obj); //IllegalAccessException EDIT: as has been commented by aperkins, both accessing the field, setting it as accessible and retrieving the value can throw Exceptions, … Read more
You use: public scope to make that property/method available from anywhere, other classes and instances of the object. private scope when you want your property/method to be visible in its own class only. protected scope when you want to make your property/method visible in all classes that extend current class including the parent class. If … Read more
Assuming no SecurityManager is preventing you from doing this, you can use setAccessible to get around private and resetting the modifier to get rid of final, and actually modify a private static final field. Here’s an example: import java.lang.reflect.*; public class EverythingIsTrue { static void setFinalStatic(Field field, Object newValue) throws Exception { field.setAccessible(true); Field modifiersField … Read more
The official tutorial may be of some use to you. Class Package Subclass(same pkg) Subclass(diff pkg) World public + + + + + protected + + + + no modifier + + + private + + : accessible blank : not accessible