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T.M.A. - Too Many Acronyms
3:31The Java ecosystem contains a lot of acronyms. In order to get things working locally you are going to need to get familiar with them.
The Java community and
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ecosystem consists of a whole slew
of acronyms and, unfortunately,
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if you're gonna follow along, you're
gonna need to get familiar with them.
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We're about to start on a long line of
them so try not to let it overwhelm you.
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I will make sure that they're in
the teacher's notes every time I
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introduce one.
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Remember to check your video controls and
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slow me way down if you
start to feel lost.
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Almost every programming language or
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platform provides you with tools to
do work locally on your computer.
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These tools are usually grouped under the
title Software Development Kit, or SDK.
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They are also sometimes
referred to as devkits.
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The Java language has an SDK,
and it's made up of many things,
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application servers, debuggers,
code samples, and documentation.
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There's an extended subset of this SDK
that is known as the Java Development Kit,
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or JDK.
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When the term JDK is used, we are
referring to this subset, the Java SE, or
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Standard Edition, Development Kit.
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You've used a couple of tools
already out of the JDK.
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The Java documentation provides
a great overview of the JDK.
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So let's go check it out.
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Now remember,
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I warned you about the upcoming
acronyms so let's not get overwhelmed.
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I just wanted to show you a couple
things in this really nice graphic.
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So you'll see here this is the entire JDK.
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And up here a couple tools
you're familiar with, right?
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There's Java and there's javac, and you'll
get familiar with the rest of these.
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And in here, is what is known as the JRE,
the Java Run Time Environment.
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It contains libraries
that we've been using.
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See, here's the collections, right,
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and there's others that we'll continue
to explore over our Java adventures.
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Now the Java language is up here.
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This is where we'll be using the ifs and
the whiles and that sort of thing.
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So the main thing to note here is that you
can actually have the JRE all by itself.
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And some people ship their
applications with just the JRE,
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without actually having
their users install the JDK.
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But, since we're developers,
we'll need the JDK for sure.
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So remember, when we go to download
this we want the JDK and not the JRE.
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I put a link to this wonderful
graphic in the teacher's notes.
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Feel free to click around,
these are all links.
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All right, so
let's go over that one more time.
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The Java Platform provides two
main software products, the JDK or
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the Java SE Development Kit and the JRE,
or the Java SE Runtime Environment.
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The JDK contains the JRE.
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The JRE contains the Java SE API, or
application programmer interface.
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The API is the libraries like the
collections framework, like the list, set,
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and map that we've been using.
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Those libraries are also
sometimes referred to as
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the Java Class Library, or JCL.
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When we talk about the JDK, we will be
talking about the official Oracle JDK.
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However, you should know that
this is an open platform, and
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there are numerous JDKs available.
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I've linked to a list of
them in the teacher's notes.
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Phew, I told you, there were TMA,
too many acronyms.
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One very important feature of the JRE
is something we haven't touched on yet.
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Of course, it's another acronym.
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It's the JVM, or the Java Virtual Machine.
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Let's learn a bit more about that
right after this quick exercise.
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