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In this noncompliant code example, if one thread repeatedly calls the method oneassignValue(), and another thread repeatedly calls the method twoprintLong(), then method twoprintLong() could occasionally print a value of i that is neither zero nor the value of the argument j.

class LongContainer {
  private long i = 0;

  void oneassignValue(long j) {
    i = j; 
  }

  void twoprintLong() {
    System.out.println("i = " + i);
  }
}

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class LongContainer {
  private volatile long i = 0;
 
  void oneassignValue(long j) { 
    i = j; 
  }
 
  void twoprintLong() {
    System.out.println("i = " + i);
  }
}

It is important to ensure that the argument to method oneassignValue() is obtained from a volatile variable or as a result of explicitly passing an integer value. Otherwise, a read of the variable argument may itself expose a vulnerability.

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