Class declaration with one method : Defining Class « Class Definition « Java Tutorial

public class MainClass
   public static void main( String args[] )
      GradeBook myGradeBook = new GradeBook(); 


class GradeBook
   public void displayMessage()
      System.out.println( "Welcome to the Grade Book!" );

Welcome to the Grade Book!

5.1.Defining Class
5.1.1.What Is a Java Class?
5.1.3.Defining Classes: A class has fields and methods
5.1.4.Creating Objects of a Class
5.1.5.Checking whether the object referenced was of type String
5.1.6.Class declaration with one method
5.1.7.Class declaration with a method that has a parameter
5.1.8.Class that contains a String instance variable and methods to set and get its value
5.1.9.Class with a constructor to initialize instance variables
5.1.10.Specifying initial values in a class definition