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Onto our next built-in annotation,
deprecated.

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This annotation is placed on methods or
classes that are still functional but

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will be phased out in a future release.

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So, developers should update their
code base as soon as is reasonable.

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If at all possible,

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we don't want to break existing code that
is using a method we want to deprecate.

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Let's take a look at an example to
illustrate how using the deprecated

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annotation can make us
courteous developers.

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In the deprecated package of
the same workspace's project,

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consider the Seller class.

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It has a single method in there called,
placeAdInNewspaper().

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Upon updating our class for
the next release, we decide we wanna

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phase out this method and provide a new
method called postInCraigslist().

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Adding the new method is
pretty straightforward.

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Let's create that now.

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I'll make this one public void as well,
postInCraigslist().

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I'll add a couple parameters,
just for demonstration purposes.

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We'll get the text for the ad in there,

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as well as a list of images that we might
want to include with our Craigslist post.

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And then here,
we'll do all of the new school stuff.

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Since I've newly introduced the list and
image classes to this file,

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I'll add those import statements now.

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For the list, that's java.util.list.

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And for image, that's java.awt.image.

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You might think that if we are going
to get rid of the old method anyway,

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we should just delete it now.

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But, if we do that, then another developer
who is using our updated library,

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might find herself scrambling
because her code no longer compiles.

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I can demonstrate that now.

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Down in my console,
I'll switch to the source directory.

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And I will compile with the javac command.

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And when I do that,

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you can see that an error has
indeed occurred in the main class.

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And this is because right here, I have
called the method placeAdInNewspaper().

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A better solution,
would be to communicate to

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other developers that the newspaper
method is going to be phased out.

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To do this, we can add
the deprecated annotation to it.

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This will force the compiler
to generate a warning.

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The nice thing about this being a warning,
is that it won't prevent our code from

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compiling, but
it will give us an informative message.

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[SOUND] Another cool thing is that most
IDEs will give you a visual indication of

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this wherever you try to
call a deprecated method,

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usually by crossing out the method call.

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This is a good heads up to other
developers that their code should be

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updated, because a future release
will no longer have this method.

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Kind of like your highschool teacher,
crossing out a phrase on your research

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paper, indicating that you need
to use alternative wording.

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Instead of deleting the message,
which I will undo now,

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let's add the deprecated annotation to it.

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And now, when we recompile,
we get a nice heads up from the compiler.

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Indeed, this is much nicer than a broken
application that does not compile.

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It gives developers a chance to update
their code to use the preferred methods.