What are inner classes in Java?

Java allows writing classes within classes and the class which is written inside another is known as inner class.

• Inner classes are a kind of security mechanism in Java.
• You can declare an inner class private once you do it cannot be accessed from an object outside the class.

Java supports three kinds of inner classes.

• Inner Class
• Method-local Inner Class
• Anonymous Inner Class

Example

Public class Outer{
   class Inner{
   }
}