AP Computer Science 1.3 Classes and Objects

or upgrade to queen stats which of the following should

be declared as a static variable I've number number of

bees is queen all right What the potential answers Here

we go we're on the numeral time and okay we're

being asked which variable or variable should be that flared

static before we can answer this let's examine what static

variables are what they do and why they're important Well

a static variables one whose value will remain constant across

an entire class of objects If we change the variables

value for one of the objects it'll reflect across every

object of that class Well to visualize this let's imagine

you have a workshop where you build coffee tables and

you're writing a program to keep track of the tables

you've made you might have a class called coffee table

and assign it Some data members such as material type

table length and numb legs will make numb legs a

static variables for each table that gets created will need

to declare the material type length and number of legs

thiss once made a pine fifty inches long and has

four legs solid This one's cherry wood very fancy thirty

inches long and has four legs and this one is

a metal table thirty inches long and with four legs

Wait you know what That first one isn't pine it's

oak We need to go back and change it There

we go in this example the material type variable is

not static so when we change that variable for one

object it doesn't affect the others of that class Numb

legs however has been declared a static If we change

that variable for any coffee table object it affects all

of them on your snacks are all over the floor

In the case of the bees we've got three variables

and move to the side which would be more was

appropriately status we'll hide number is a variable we're using

to identify which hive each particular be belongs to If

this were static every bee would belong to the same

single hive that wouldn't work is a static variable Things

would get too crowded really quickly Yeah is clean also

wouldn't work for a couple of reasons First the question

specified that abi's clean status could not be changed so

that's a deal breaker but just as importantly even if

we could change it having that variable static would mean

everyone would either be a queen or no one would

be anything at all and that's not gonna work for

us either So now we're left to look at number

of bees which is intended to be a counter keeping

track of exactly that If number of these were static

and we update this variable for one be it affects

all of them So that's pretty useful of our possible

answer b is the only one that fits the bill

we've identified the on ly number of b should be

static before we go it's important to remember the distinction

between static variables and final variables here the sound similar

but as we learned a static variable is one that

remains the same across every object in a class If

it changes for one object it changes for every object

in that class where's final variables which were not used

in this question are to find once and never change

their values you can consider final variables to be set

in stone like you're no political uncle on facebook Yeah 00:03:19.92 --> [endTime] okay