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This lesson is going to be really short, I'm sure at some point in the future you're going to come

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across atomic types, and this is a perfect time to explain what it is.

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Atomic types let you safely update variables across multiple threads.

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They're also cleaner and faster than locks.

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So if you're a variable is being updated by many threads, then simply declaring it as an atomic can

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make your code thread safe.

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Some now declare this as an atomic integer.

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Which is equal to a new atomic integer.

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With the value of zero.

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And now this is not a primitive type anymore, it's a class type.

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So instead of saying counter plus plus, we're going to say counter and we're going to call the ad and

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get method from the atomic energy class.

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And so what the ad part is going to do is during its run, it's going to add one.

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And what Dick Gephardt does is it returns the updated value.

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And now we don't have to use locks anymore.

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If we rerun the code.

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Even across multiple threads, our calendar gets updated correctly.

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And so why were we able to remove the lock?

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Well, atomic variables are special in the sense that when this atomic variable is being accessed and

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updated by one thread, and let's say another thread tries to join in, it's going to say, Whoa, whoa,

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whoa, wait your turn.

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And so they're pretty special in that sense.

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So to keep it short, whenever possible, they were using an atomic type over a lock.

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It's cleaner and typically faster, so we can remove this lock parameter right here.

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We don't need it anymore.

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I'm here as well, and you can remove the re-entering clock declaration.