what is checked and unchecked exception code example

Example: Unchecked exception

All subclasses of RuntimeException are called unchecked exceptions. 
These are unchecked exceptions because compiler does not checks if a method 
handles or throws exceptions. Program compiles even if we do not catch the 
exception or throws the exception. If an exception occurs in the program,
program terminates. It is difficult to handle these exceptions
because there may be many places causing exceptions.
Example : 
1) Arithmetic Exception
2) ArrayIndexOutOfBoundsException
3) ClassCastException
4) IndexOutOfBoundException
5) NullPointerException
6) NumberFormatException
7) StringIndexOutOfBounds
8) UnsupportedOperationException