static data and static methods in java

1class JavaExample{
2   private static String str = "BeginnersBook";
3
4   //Static class
5   static class MyNestedClass{
6	//non-static method
7	public void disp() {
8
9	   /* If you make the str variable of outer class
10	    * non-static then you will get compilation error
11	    * because: a nested static class cannot access non-
12	    * static members of the outer class.
13	    */
14	   System.out.println(str); 
15	}
16
17   }
18   public static void main(String args[])
19   {
20       /* To create instance of nested class we didn't need the outer
21	* class instance but for a regular nested class you would need 
22	* to create an instance of outer class first
23        */
24	JavaExample.MyNestedClass obj = new JavaExample.MyNestedClass();
25	obj.disp();
26   }
27}