16- Adders

Jul 03, 2026 22:41 · 2:09 · English · Whisper Turbo · 2 Sprekers

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S… Speaker 2 (16- Adders)

So atomic objects are great for implementing counters,

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but if you have multiple threads updating a value frequently,

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it's better to use one of the other classes in Java.

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They're faster than atomic types.

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So we have long adder for adding long values

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and double adder.

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Let me show you how they work.

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So we have the same code as before.

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This is the code that has a race condition.

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So when we run this program,

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we see this weird number over here.

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Let's solve this problem using an adder class.

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So in the last video,

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we replaced this integer field with an atomic adder.

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Now we're going to replace this with a long adder.

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And then we set this to a new long adder.

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All right.

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Now in our getter,

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we call the int value method.

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This will return the result as an integer.

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We also have byte value,

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short value,

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double value,

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and so on.

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S… Speaker 2 (16- Adders)

Internally, this long other object keeps an array of counters that can grow

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on demand.

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So we don't have a single place in memory where our value is stored.

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We have a bunch of array cells each holding a counter value.

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So different threads can modify this counter variables concurrently.

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That's why these other classes are faster than atomic types because

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they allow more throughput.

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So here we can call

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int value method but internally this method is going to call another

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method called sum which is going to add up all these counter values

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and return the result.

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Now the int value will call this method and then convert the result to

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an integer.

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Now in our increment method we call increment.

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We also have add for adding a long value.

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We have decrement,

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we have reset,

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and so on.

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So let's call the increment method.

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That's all we had to do.

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Let's run our program.

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The race condition is gone.

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S… Speaker 2 (16- Adders)

So if you have multiple threads updating a value frequently,

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prefer the adder classes to atomic types.

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