public Counter( String threadName )
    {
        super( threadName );           // What if we omitted this line?
        System.out.println( this );
        start();                       // Could we have started it in Client?
    }

          // override Thread's run method
    public void run()
    {
        try
        {
            while ( currentValue < 5 )
            {
                System.out.println( getName() + ": " + ( currentValue++ ) );
                Thread.sleep( 500 );
            }
        }
        catch ( InterruptedException e )
        {
            System.out.println( getName() + " interrupted." );
        }
        System.out.println( "Exit from " + getName() + "." );
    }

    public int getValue()
    {
        return currentValue;
    }
}

public class Client
{
    public static void main( String args[] )
    {
        Counter counterA = new Counter( "Counter A" );
        System.out.println( "Exit from Main Thread." );
    }
}