Lesson 31: Void Methods

Lesson 31:

Void Methods

AP Computer Science - Unit Four

Void Methods

Big idea: Take a large complicated problem and break it down into small pieces called methods. Each of these pieces does one specific job in the program.

AP Computer Science - Unit Four

Void Methods

Methods you have used: .compareTo("zebra") .length() .equals("Howdy") .charAt(1)

AP Computer Science - Unit Four

Void Methods

Method These pieces of code are given a name. The method goes above main. The name lets Java find the correct piece of code

AP Computer Science - Unit Four

Void Methods

Example: Write a method to print "java" public void printJava (){ System.out.println("java"); }

AP Computer Science - Unit Four

Void Methods

So how do we use this? In Main: public static void main (String str[]) throws IOException { }

printJava();

AP Computer Science - Unit Four

Void Methods

So why do we use this? Code Reuse You can set up a really long tricky bit of code and then every time you need to run it you type in: doTrickyStuff();

AP Computer Science - Unit Four