222: Mainline

You know that you can refer to an instance-variable value directly by using the field-selection operator. For example, suppose that you have defined the Attraction class with a minutes instance variable that records the duration of an entertainment attraction in minutes. You can refer to the value of that instance variable in a particular attraction, x:

x.minutes 

Alternatively, you can refer to an instance-variable value indirectly by defining an instance method that returns the instance-variable value. In the following Attraction class definition, for example, an instance method named getMinutes returns the value of the minutes instance variable:

public class Attraction {
 // First, define instance variable:
 public int minutes;
 // Define zero-parameter constructor:
 public Attraction () {minutes = 75;}
 // Define one-parameter constructor:
 public Attraction (int m) {minutes = m;}
 // Define getter:
 public int getMinutes () {     
  return minutes;               
 }                              
} 

With getMinutes defined, you have another way to refer to the value of the minutes instance variable of a particular attraction, x:

x.getMinutes()