public MockClock incrementByMicroseconds(long incrementInMicros){
  if (incrementInMicros < 1)   throw new IllegalArgumentException("The clock increment must be positive");
  ticker.accumulateAndGet(incrementInMicros,null);
  return this;
}

public MockClock incrementByMicroseconds ( long incrementInMicros ) { if ( incrementInMicros < 1 ) throw new IllegalArgumentException ( "The clock increment must be positive" ) ; ticker . accumulateAndGet ( incrementInMicros , null ) ; return this ; }
increment the clock by the specified number of microseconds .
