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import java.util.concurrent.atomic.AtomicBoolean;

final class Flag {
  private AtomicBoolean flag = new AtomicBoolean(true);
 
  public void toggle() { 
    boolean temp;
    do {
      temp = flag.get();
    } while(!flag.compareAndSet(temp, !temp));
  }

  public AtomicBoolean getFlag() { 
    return flag;
  }
}

This ensures that updates to the variable are carried out The flag variable is updated using the compareAndSet() method of class AtomicBoolean. All updates are made visible to other threads.

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In this noncompliant code example, the two fields a and b setValues() method may be set invoked by multiple threads , using the setValues() method.to set the a and b fields,

final class Adder {
  private int a;
  private int b;

  public int getSum() {
    return a + b;
  }

  public void setValues(int a, int b) {
    this.a = a;
    this.b = b;
  }
}

The getSum() method may return a different sum every time it is invoked from different threads. For instance contains a data race. For example, if a and b currently have the value 0, and one thread calls getSum() while another calls setValues(1, 1), then getSum() might return 0, 1, or 2. Of these, the The value 1 is unacceptable; it is returned when the first thread reads a and b, after the second thread has set the value of a but before it has set the value of b.

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The issues described in the previous noncompliant code example can also arise occur when the fields a and b of type int are replaced with atomic integers.

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