Java™ How to Program, Seventh Edition

3.3. Declaring a Class with a Method and Instantiating an Object of a Class

We begin with an example that consists of classes GradeBook (Fig. 3.1) and GradeBook-Test (Fig. 3.2). Class GradeBook (declared in file GradeBook.java) will be used to display a message on the screen (Fig. 3.2) welcoming the instructor to the grade-book application. Class GradeBookTest (declared in file GradeBookTest.java) is an application class in which the main method will use class GradeBook. Each class declaration that begins with keyword public must be stored in a file that has the same name as the class and ends with the .java file-name extension. Thus, classes GradeBook and GradeBookTest must be declared in separate files, because each class is declared public ...