Dr Heinz Kabutz

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Thread Safety with Phaser, StampedLock and VarHandle

Every major Java version introduces a new and better way of managing state. Java 7 gave us Phaser as a replacement for CountDownLatch and CyclicBarrier. Hardly any programmers know how it works, even though we are now on Java 11. Java 8 gave us StampedLock, useful as a lighter read "lock" when building concurrent classes. Again, not very widely known, but lots of use cases. Java 9/10/11 introduced VarHandle as an escape latch for the Unsafe addicts. In this talk we will show all three concepts and explain when each should be used.