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Have you ever wonder what is the default modifier in Java? And what is its scopes?

Modifier
public
protected
no modifier (package scope or package-private)
private

Access level modifiers determine whether other classes can use a particular field or invoke a particular method. There are two levels of access control:
  • At the top level—public, or package-private (no explicit modifier). The top level here means Class level
  • At the member level—public, private, protected, or package-private (no explicit modifier).
>> A class may be declared with the modifier public, in which case that class is visible to all classes everywhere. If a class has no modifier (the default, also known as package-private), it is visible only within its own package

>> At the member level, you can also use the public modifier or no modifier (package-private) just as with top-level classes, and with the same meaning. For members, there are two additional access modifiers: private and protected. The private modifier specifies that the member can only be accessed in its own class. The protected modifier specifies that the member can only be accessed within its own package (as with package-private) and, in addition, by a subclass of its class in another package.

Example:


Classes and Packages of the Example Used to Illustrate Access Levels
The following table shows where the members of the Alpha class are visible for each of the access modifiers that can be applied to them.
Visibility
Modifier Alpha Beta Alphasub Gamma
public Y Y Y Y
protected Y Y Y N
no modifier Y Y N N
private Y N N N

 

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