Java Programming :: Declarations and Access Control

gistfile1.txt

Ref: http://www.indiabix.com/java-programming/declarations-and-access-control/

Access modifiers dictate which classes, not which instances, may access features.
Methods and variables are collectively known as members. Method and variable members are given access control in exactly the same way.

private 
    makes a member accessible only from within its own class

protected 
    makes a member accessible only to classes in the same package or subclass of the class

default 
    access is very similar to protected (make sure you spot the difference) default access makes a member accessible only to classes in the same package.

public 
    means that all other classes regardless of the package that they belong to, can access the member (assuming the class itself is visible)

final 
    makes it impossible to extend a class, when applied to a method it prevents a method from being overridden in a subclass, when applied to a variable it makes it impossible to reinitialise a variable once it has been initialised

abstract 
    declares a method that has not been implemented.

transient 
    indicates that a variable is not part of the persistent state of an object.

volatile 
    indicates that a thread must reconcile its working copy of the field with the master copy every time it accesses the variable.