Java Inner Classes

Java Inner Class

• It is possible to define a class within another class, such classes are known as nested classes.
• The scope of a nested class is bounded by the scope of its enclosing class. 
• Thus, if class B is defined within class A, then B does not exist independently of A.
• A nested class has access to the members, including private members, of the class in which it is nested.
• However, the enclosing class does not have access to the members of the nested class. 
• A nested class that is declared directly within its enclosing class scope is a member of its enclosing class. It is also possible to declare a nested class that is local to a block.

Types of Nested Class -

Basically there can be two types of nested class -

  1.Static Nested class.

  2.Non-Static Nested class

      1. Static nested Class

•  A static nested class is one that has the static modifier applied.
• Because it is static, it must access the members of its enclosing class through an object. 
• That is, it cannot refer to members of its enclosing class directly. Because of this restriction, static nested classes are seldom used.

     2. Non-Static nested Class

• The most important type of nested class is the inner class.
•  An inner class is a non-static nested class.
• It has access to all of the variables and methods of its outer class and may refer to them directly in the same way that other non-static members of the outer class do.

Example -

Output -

Making Inner class Static

Example

Output-