New to Java

Hi Guys today i was practicing writing small program using fully Quallified names for the classes.Below is my Class No.1

public class Chapter3_2
{
	public void displayMessage(String coursename)
	{
	String message = String.format("Welcome to Niit Your Course is %s",coursename);
	System.out.printf("%s",message);
	}
};

however when right the main class using fully quallified name i faced a problem with name of the Chapter3_2 class fully quallified name. I have no idea what is fullyqualified name for default package. I am posting the Incomplete code fpr your referance. Appreciate our concern.Thanks in advance and Seasons greating to all of you.