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| SESSION 3 Part5 |
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Java's API |
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Next, let's take a quick look at
Java's functions
Java has
many useful functions
set up as standard class library.
You can do many things by using this
without making anything yourself.
It is actually called
API（Application Program Interface）
but,
it means almost the same as library,
just from different view point.
There are many cases like this with
computer.
(and in the real world as well?)
For your reference, let's take a look at
"just small part" of API which is
frequently used.
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Part of Java's API |
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| API |
Contents |
| java.applet |
Processing with applet |
| java.awt |
Processing with
graphics |
| java.io |
Processing with
input/output for files |
| java.lang |
Basic processing |
| java.net |
Processing with network |
| java.security |
Processing with
security |
| java.util |
Processing with many
useful things |
| javax.crypto |
Processing with code |
| javax.swing |
Processing with screen component such as window |
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In program, it is called
"processing" to run and get the
result.
Here, you could read as processing = function.(japanese
only?) |
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Is that it?
Not many, huh.
Don't scare me. |
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This is just like an index.
There are many processing inside,
you see.
For java.net,
there are many processing with
network…
something like that.
With this table alone,
there are millions of functions which
could make you ｆeel dizzy.
You want to have a closer look?
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Easy one would be…
For example, Java.lang.Math
deals with basic calculation,
and look at "Method Overview"
in online API document.
See how many calculation methods
are written?
You can calculate easily by using this. |
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Let's see |
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Oh my Gosh…
There are
so many…
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And,
this document shows
the overview.
They are shown as layers, so
as you click
you can see
all of
Java's standard equipment. |
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Oh no!!!
there are so many
English here, too.
When I click,
there are more strange
English!
Oh, my Gosh,
they are like magic words.
I don't understand,
I am in the darkness…
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Ha ha,
I am sorry.
I just wanted to show you
that there are many functions.
We are going to use this function
to create a game in the future.
Once you get used to it,
you will be able to understand.
We will take a look step by step
later.
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But,
I can't remember
stuff like this.
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Ahhhhh… |
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Was that a
bit too much? |
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Don't worry,
you don’t have to remember.
When you need,
you just need to look up the part
you want to know.
Like dictionary, you know?
Indeed,
it is difficult to know what is where
because there are so many of them,
though.
If you used integrated
development environment
that I explain
next,
it makes your life a lot easier, so
you don’t need to stress too much.
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Oh I see
C'mon,
don't scare
me buddy! |
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That was
real quick… |
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All right,that's us today.
We are going to create
development environment
next time.
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Wow!!
It is all happening now.
Thank you very much.
See you again at the
next lesson. |
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| Runtime
is necessary to operate Java program |
Runtime soft designed for Java called JRE is
needed to run the soft created by Java.
It needs to be installed in the computer that
runs.
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| Java can be operated with many environments once created |
The soft made with Java can be operated in many
environments once created,
thanks to the function of byte code and runtime.
There is no need to create for Windows or Mac
separately.
When a game is delivered, it can be adapted to
many environments with the same program, it can
be played by many people.
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| Java has
many functions |
There are many useful processing (functions)
already prepared in Java.
There are many functions that require expert
knowledge to create such as encryption
processing,
so you don't need to create by yourself.
You can use this to create a game smoothly.
We are going to use them later to create a game. |
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| Terms for today |
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Extension |
Runtime |
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Java SE |
JRE |
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Byte code |
API |
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| We are going to introduce Java later on the regular basis. |
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