小编Pav*_*zky的帖子

出于教育目的,我正在编写一个简单的版本AtomicLong,其内部变量受到保护ReentrantReadWriteLock.这是一个简化的例子:

public class PlainSimpleAtomicLong {

  private long value;

  private final ReentrantReadWriteLock rwLock = new ReentrantReadWriteLock();

  public PlainSimpleAtomicLong(long initialValue) {
    this.value = initialValue;
  }

  public long get() {
    long result;

    rwLock.readLock().lock();
    result = value;
    rwLock.readLock().unlock();

    return result;
  }

  // incrementAndGet, decrementAndGet, etc. are guarded by rwLock.writeLock()
}

我的问题:由于"value"是非易失性的,其他线程是否有可能通过不正确的初始值来观察PlainSimpleAtomicLong.get()？例如,线程T1创建L = new PlainSimpleAtomicLong(42)并与线程共享引用T2.为T2保证遵守L.get()为42？

如果没有,包装this.value = initialValue;到写锁定/解锁会有所作为吗？