/* 
 *  This program demonstrates how exceptions can be caught which thrown from another method.  It also demonstrates
 *  how Exceptions are caught based on type and subtype.
 *
 *  In this case, we have two catches, ArithmeticException and Exception, to see where a type of Exception will be caught.
 *  Run this program using different values for a and b between 0 and 3 each.
 */
public class Exception3
{
	public static void main(String[] args)
	{
		int a=1, b=1; 		// change these and see what happens
		try{
			method1(a);		// method1 can throw an exception, in this case it will throw
		}					// a NullPointerException and be caught in the 2nd catch block
		catch(ArithmeticException e)  {
			System.out.println("exception is an ArithmeticException type");
							// handle exception from method1 if it is an ArithmeticException
		}
		catch(Exception e)	{  // handle all other types of Exceptions
			System.out.println("exception is not an ArithmeticException type");
		}
		method2(b);			// method2 will throw an exception but will be caught within method2
	}						// rather than here
	
	public static void method1(int x) throws ArithmeticException,NullPointerException,Exception
	{				// no try or catch blocks here, any Exception thrown terminates this method
		if(x==0) throw new ArithmeticException("x=0");
		else if(x==1) throw new NullPointerException("x=1");
		else if(x==2) throw new Exception("x=2");
		else System.out.println("No exception thrown from method1");
	}
	
	public static void method2(int x)
	{
		try			// if an Exception is thrown, catch it in one of the following catch blocks
		{
			if(x==0) throw new ArithmeticException("x=0");
			else if(x==1) throw new NullPointerException("x=1");
			else if(x==2) throw new Exception("x=2");
			else System.out.println("No exception thrown from method2");		
		}
		catch(ArithmeticException e) {
			System.out.println("ArithmeticException caught in method2 with " + e);
		}
		catch(Exception e) {		// will catch the NullPointerException or the Exception
			System.out.println("Exception caught in method2 with " + e);
		}	
		System.out.println("reached this point after the try-catch blocks");	
	}

}