/** Next low number guess test. */
 @Test
 public void nextLowNumberGuessTest() {
   when(rangeGenerator.generateRange(4)).thenReturn(new Range(16, 32));
   long nextHighNumber = nextGuess.nextLowNumber(16);
   assertThat(nextHighNumber, is(16L));
   verify(rangeGenerator).generateRange(4);
 }
 /** Next high number guess test. */
 @Test
 public void nextHighNumberGuessTest() {
   when(rangeGenerator.generateRange(6)).thenReturn(new Range(64, 128));
   long nextHighNumber = nextGuess.nextHighNumber(64);
   assertThat(nextHighNumber, is(128L));
   verify(rangeGenerator).generateRange(6);
 }