Welcome to CSE 131 This is a very short exercise that you do as part of Lab 0 Review the following slides to learn the anatomy of a Java class program. There is an exercise for you to complete as part of Lab 0 to test your knowledge of these slides. You can repeat the exercise as many times as you need until you are able to recognize the different parts of a Java program.

Anatomy of a Java program 2 A Java program can have many packages. Each package contains a set of related classes. For example, a baseball package might have a Pitcher, Batter, and Scorekeeper class The name of this package is lab0

Anatomy of a Java program 3 A class describes the behaviors of an object. This class is called RobotInstructions It has just one kind of behavior which is to act Other objects have more behaviors For example, a Pitcher might throw a ball, catch a ball, etc.

Anatomy of a Java program 4 The behaviors in a class are divided into methods This method is named “act” A Pitcher might have a method to throw a ball, catch a ball, etc.

Anatomy of a Java program 5 For a method to do its job, it sometimes needs information You see here an “incoming parameter” – a “robot” that is provided to the “act” method. The act method can then issue instructions to the robot

Anatomy of a Java program 6 This line of code sends a message to an object to tell it to do something The object here is “robot” – it is the thing we are telling to do something The method call is “forward” – we are asking the robot to go forward This method call requires some information – how far forward should it go? The value of 100 is the outgoing parameter, sent to the forward method, addressed to the robot.