Processing: Creative Coding and Computational Art

Hopefully you noticed that the only difference between the good and bad code is the
absence of the this keyword at the beginning of the bad code assignments. If you don’t
use the this keyword, the compiler uses the local parameters on both sides of the assignment
operator.
The special keyword this refers to the class itself. Thus, this.meatType is the property,
not the parameter of the same name. As I mentioned, if you don’t use the keyword this,
the compiler will only use the local parameter within the constructor block—so an assignment
like meatType = meatType doesn’t pass a value to the property, but just uselessly
assigns the parameter value back to the parameter—meaning nothing really happens. I
realize that if this is totally new to you, it may seem like an obscure point, but it really isn’t.
Is there any way to avoid using the this keyword? Well, there is, actually. If I had used distinct
property and parameter names, I could have avoided using the this keyword. For
example, the following constructor could be safely substituted for the second constructor
in the BurritoRecipe class example:
//basic burrito recipe--add toppings later
BurritoRecipe(String tortFlavor, String bType, String mType){
//initialize properties
tortillaFlavor = tortFlavor;
beanType = bType;
meatType = mType;
}
I still could use the this keyword in front of the properties on the left of the assignments
if I wanted to, but it is not required any longer. Ultimately, you can do your constructor initializations
either way: using the same named properties and parameters and the this keyword
in front of the properties, or keeping the property and parameter names distinct. In
my humble opinion, using the same names for the properties and parameters ultimately
makes things simpler, and also helps you to see what parameter to assign to what property.
But not everyone would agree with me. When you start looking at other people’s code,
you’ll see this handled both ways—even though I think I’m right.
Methods
After the constructors, there is a long list of methods, in the following style:
int getSize() {
return this.size;
}
void setSize(int size) {
this.size = size;
}
OBJECT-ORIENTED PROGRAMMING
In OOP, there is a convention to structure methods utilizing the get/set prefix appended
to the property names (commonly referred to as get/set methods, or “getters” and
“setters”), as illustrated in the preceding code. Not all your methods will be getters and
setters, but generally it is desirable to have a get and set method for each property. In pure
OOP (which you’re not totally burdened with here), the idea is that a class’s properties
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