/* This class is an example demonstrating that you can code a
 * class that works with, and without, the presence of other classes.
 * Use this if you want to take conditionally take advantage of
 * an 'optional' class,
 * like javax.* classes that may not be present everywhere.
 *
 * http://www.bolthole.com/java/
 */

public  class parent { 
	boolean have_aux=false;
	aux testinstance=null;
	static void debug(String msg){
		System.out.println(msg);
	}


	public parent(){
	
		// Here is the actual "test" for the aux class.
		// It doesnt do anything we care about, but
		// it DOES throw an exception if class not loadable.
		// Otherwise, with 'new', there is no exception that
		// we can catch
		try {
			Class.forName("aux");
		} catch (ClassNotFoundException err){
			debug("Note: aux class not available. ");
			return ;
		}

		testinstance=new aux();
		have_aux=true;
		debug("main class has loaded 'aux' class");
	}

	void dostuff(){
		debug("In dostuff(). Here is some regular stuff");
		
		if(have_aux){
			debug("We have aux. main instance calling 'aux' class");
			testinstance.extrastuff();
		} else {
			debug("Sorry, aux class is not loaded. No extra stuff");
		}
		
	}

	public static void main(String args[]){

		parent myinstance=new parent();
		
		debug("New instance of parent created. Now doing stuff...");
		myinstance.dostuff();
	}
}