Java Programming Tutorial - 5 - Variables Video Lecture - Java Programming

what's up guys is Bucky welcome to your
fifth java tutorial and in this story
I'm going to talking to you guys about
something called a variable now what
variable in Java is is pretty much like
a placeholder for something else now if
you remember from math class back in
like seventh grade or whatever whenever
you had a variable and it was usually
named something like X you could have it
set to a value like 73 and then whenever
you use X in a program or a calculation
or something X will take the value of 73
and that's pretty much the same exact
thing a variable does in Java you assign
something called a variable name to
value then whenever you use the variable
people know that it's not really the
variable but actually stands for that
value so let's go ahead and make one of
these in Java now to make one of these
in Java the first thing that you need to
do is tell Java what kind of variable
you're going to be working with and
there's a bunch of different kinds of
variables you can work with in Java you
can use integers like 3 you can use
integers with decimal points like 3.14
you can use letters like s you can use
strings of characters like Bucky and so
once you have that decided you need to
have a way to tell Java what kind of
variable you're working with so it
doesn't get confused so we're we're
going to be working with today is
something called a double now what a
double is is it's a little bit above
it's a keyword that tells Java all right
you're going to be working with a number
but this number can have a decimal point
as well so um after you tell Java what
kind of variable you want to work with
you got to give it a name so let's go
ahead and say we're going to be working
with a variable called double and we're
going to name it tuna now after you have
a variable called tuna you need to give
a value so go ahead and write 2
none which is a variable name and then
go ahead and press equals
now what equals is here is something
called the assignment operator and what
it does is assign a value to tuna so
what that we are we're going to assign
it let's go ahead and write five point
28 my favorite number five point 28 so
here's what we did so far we told Java
that we're going to be working with a
variable called tuna and then it's going
to be a double meaning that has um
numbers on both the left and right hand
side of the decimal point again an
integer is only a whole number like
eight ten negative four and a double has
a fraction like five point two eight
eight point one eight so again we told
that tuna is double it has a fraction
next we said all right what's the value
of tuna well here's the name here's the
assignment operator and here's the value
tuna equals five point two eight now we
have a variable that has the value of
five point two eight that we can throw
into any Java program so let's go ahead
and do that and how we do that is just
like we did before just print it out on
a screen so let's go ahead and erase
system on the type of write system dot
out dot print and in your parameters
instead of typing a string of text like
this is a strength all we have to do is
type the word or the name of the
variable such as tuna and that would
print tuna out on the screen don't
believe me let me show you guys let's go
ahead and run this and as you can see
down in our little run box it has the
variable five point two eight so that is
how you write variables out on the
screen using Java in another cool thing
that you can do with these variables is
unless order I'll show you guys how to
write strings of text on the screen you
can also combine these variables with
strings of text so let's say we want to
write a system
got out print line and get out of here
Hoss and in our print line we're going
to say I want then go ahead and press
space actually this brings me to another
point which I will say right now there's
two different things system out and
print and system out and print line so
let me show you guys what those do right
now system dot out dot print line and
let's go ahead so what's this thing
right now
I want five point two eight what do you
want five point two eight movies I want
five point two eight movies makes no
sense but just deal with it now let me
show you guys what this does and I'll
show you guys why it does it let's go
ahead and run this and it says okay we
printed three things but only is on one
line I want five point two eight movies
and let me show you guys why this is
there's two different print statements
that you guys learn so far a system out
print what you see in the first two
lines and a system out print line what
you see in the next line well a print
statement does a basic print with no
line is it says are a Java we want to
print this but we want to stay on the
same line and it says all right so just
stay on the same line stay on the same
line and then after this move to the
next line so after you have print line
what it would do is move the cursor to
the next line so if you printed anything
after this it would show up on the next
line don't believe me let me show you
guys
system.out.print and it can even have a
basic print stay memory here and let's
have apples let me go ahead and run this
and as you can see this one moves to the
new line so that's the difference
between the print statement in the print
line statement any time you use a print
statement it stays on the same line that
you're printing on such as here so this
whole thing's on the entire line
as soon as you have a print line
statement one does is when it gets the
end of printing it it moves to a new
line so that's the difference between a
print statement and a print line
statement and again that's your quick
tutorial on how to use variables again
this is called declaring a variable this
is called assigning a variable value
again this is the name of the variable
and this is the value this is the
assignment operator right here and
anytime you want to use a variable to
print out on your screen just write
system.out.print and then write the name
of the variable right there and it'll
print out on your screen so again that's
a quick tutorial on variables and how to
use variables in Java so thank you guys
for watching make sure to subscribe to
my channel I don't forget to check out
my next tutorial and again thank you and
I'll see you next time