java并发-Atomic

本节示例java Atomic原子操作类，很简单。

如果不使用原子操作

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public class AtomicTest {
	private static class Counter {
		private int c;

		public void incr() {
			c++;
		}

		public int getValue() {
			return c;
		}
	}

	public static void main(String[] args) throws InterruptedException {
		final Counter counter = new Counter();

		for (int i = 0; i < 1000; i++) {
			final Thread t = new Thread(() -> counter.incr());
			t.start();
		}
		Thread.sleep(3000);
		System.out.println("结果为：" + counter.getValue());
	}
}

结果是1000，但存在风险。

使用原子类

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private static class Counter {
    private AtomicInteger c = new AtomicInteger(0);

    public void incr() {
        c.incrementAndGet();
    }

    public int getValue() {
        return c.get();
    }
}

其他原子类

  1. AtomicLong
  2. AtomicBoolean
  3. AtomicReference
  4. AtomicIntegerArray
  5. AtomicLongArray
  6. AtomicReferenceArray