Notes

import java.io.*;

class A
{
public void abc() throws NullPointerException, IOException, UserException
{
int a = 50;
for(int i=1; i<=20; i++)
{
System.out.println(i);
int res = a/(a-i);
if(i==150)
throw new NullPointerException();
if(i==120)
throw new IOException();
if(i==10)
return;
if(i==80)
throw new UserException();
if(i==60)
throw new UserException("just for demo");
}
System.out.println("Program Continues....");
}
public void xyz() throws NullPointerException, IOException, UserException
{
abc();
}
public void atoz() throws NullPointerException, IOException
{
try
{
xyz();
}
catch(UserException e)
{
System.out.println("User defined exception handler");
e.display();
e.printStackTrace();
System.out.println("Reason : "+e.getMessage());
}
}
}
public class ExceptionDemo
{
public static void main(String args[])
{
try
{
A a1 = new A();
a1.atoz();
}
catch(IOException e)
{
System.out.println("Input Output Exception occured....");
}
catch(ArithmeticException e)
{
System.out.println("Divide by zero occured....");
}
catch(Exception e)
{
System.out.println("Default Exception handler....");
}
finally
{
System.out.println("THANKS");
}

System.out.println("Main method continues...");
}
}
class UserException extends Exception
{
public UserException()
{
}
public UserException(String msg)
{
super(msg);
}
public void display()
{
System.out.println("User defined exception.....");
}
}