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Odi's astoundingly incomplete notes

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JDK-1.8 simplifies atomic maximizer

With Java 8 the atomic primitives have gained a very useful function: getAndUpdate(). It takes a lamda function to atomically update the value. This simplifies previous complicated code that used compareAndSet in a loop into a one-liner.

As an example look at a piece of code that is used to keep track of a maximum value.
private AtomicInteger max = new AtomicInteger();

public void oldSample(int v) {
  int old;
  do {
      old = c.get();
  } while (!c.compareAndSet(old, Math.max(old, v)));

public void newSample(int v) {
  max.getAndUpdate(old -> Math.max(old, v));

posted on 2019-05-21 09:45 UTC in Code | 0 comments | permalink