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

1) All the subclasses of Throwable class except error,Runtime Exception and 
its subclasses are checked exceptions.
2) Checked exception should be thrown with keyword throws or should be provided 
try catch block, else the program would not compile. We do get compilation 
error.
Examples :
1) IOException,
2) SQlException,
3) FileNotFoundException,
4) InvocationTargetException,
5) CloneNotSupportedException
6) ClassNotFoundException
7) InstantiationException

I would either handle or declare. I Declare using THROWS keyword or handle by
using TRY&CATCH block. If I will use it again I would handle it. If it will
occur only once than I would use THROWS keyword