The Demons Command Each Other
From Huben's Wiki
| Line 1: | Line 1: | ||
We have penetrated the mysteries of finding demon commands. Now we must seek to use those commands, and thus control our demons. | We have penetrated the mysteries of finding demon commands. Now we must seek to use those commands, and thus control our demons. | ||
| − | ==First Call== | + | ==(A) First Call== |
Place this class into Dr.Java, save, compile and run it. | Place this class into Dr.Java, save, compile and run it. | ||
<pre> | <pre> | ||
| Line 33: | Line 33: | ||
* Create another method, named speakThrice(), that calls speak() three times. Change main() to call speakThrice() two times. How many times is the world saved? Why? | * Create another method, named speakThrice(), that calls speak() three times. Change main() to call speakThrice() two times. How many times is the world saved? Why? | ||
| − | ==Calling Between Classes== | + | ==(B) Calling Between Classes== |
Click the New button to start a new Java class, place this code in it, save it and compile it. | Click the New button to start a new Java class, place this code in it, save it and compile it. | ||
<pre> | <pre> | ||
| Line 61: | Line 61: | ||
* What rule would you make to explain why sometimes you can call with just the name of a method and other times you need something more complex? | * What rule would you make to explain why sometimes you can call with just the name of a method and other times you need something more complex? | ||
| − | ==Method Calls In Real Programs== | + | ==(C) Method Calls In Real Programs== |
It is easy to identify method calls in the toy programs on this page. It is also easy to identify them in real programs. | It is easy to identify method calls in the toy programs on this page. It is also easy to identify them in real programs. | ||
| Line 86: | Line 86: | ||
* aTypeOfSound and volume are variables that are arguments for makeSound(). | * aTypeOfSound and volume are variables that are arguments for makeSound(). | ||
* sound is a variable where we store the result of animal.makeSound(aTypeOfSound, volume). | * sound is a variable where we store the result of animal.makeSound(aTypeOfSound, volume). | ||
| + | * We can be calling methods of different classes by using objects of different classes to make the calls. Notice the dot! Just like the dot when we call with a Class name. | ||
Let's look at some real code now. Here is the main from a class Cryptogram: | Let's look at some real code now. Here is the main from a class Cryptogram: | ||
