Member Inner Class

Member Inner Class A class created within class and outside method.
Anonymous Inner Class A class created for implementing interface or extending class. Its name is decided by the java compiler.
Local Inner Class A class created within method.
Static Nested Class A static class created within class.
Nested Interface An interface created within class or interface.


A non-static class that is created inside a class but outside a method is called member inner class.

Syntax:

class Outer{
 //code
 class Inner{
  //code
 }
}


class TestMemberOuter1{
 private int data=30;
 class Inner{
  void msg(){System.out.println("data is "+data);}
 }
 public static void main(String args[]){
  TestMemberOuter1 obj=new TestMemberOuter1();
  TestMemberOuter1.Inner in=obj.new Inner();
  in.msg();
 }
}

import java.io.PrintStream;
class Outer$Inner
{
    final Outer this$0;
    Outer$Inner()
    {   super();
        this$0 = Outer.this;
    }
    void msg()
    {
        System.out.println((new StringBuilder()).append("data is ")
                    .append(Outer.access$000(Outer.this)).toString());
    }
}