Wednesday, 18 November 2009

Access Control

It is a mechanism for managing visibility of

  • class members (properties , methods , constructors)
  • classes defined in a package

Visibility simply means access.It can be set to different levels
by using these keywords

When applied to class members

public :

They are accessible everywhere

private :

Can be accessed only by the code in defining class

protected :

  • Within the package : accessible everywhere
  • Outside the package , only subclasses can access

default : When nothing is specified

Accessible only within the package

When applied to class

public :

Visible inside as well as outside the package in which it is defined

default : When nothing is specified

Visible only inside the package in which it is defined