### Question:
Stats { public boolean isEmpty() { return this.stats.isEmpty(); }  void putStatisticType(Stat stat); Stat getStatisticType(String key); Set<String> getStatisticTypes(); Set<String> getStatisticKeys(); LinkedHashMap<String,Double> getStatistics(String group, String scenario, String step); LinkedHashMap<String,Double> getStatistics(String group, String scenario); LinkedHashMap<String,Double> getStatistics(String groupOrKey); Double getStatistic(String name,String group, String scenario, String step); Double getStatistic(String name,String group, String scenario); Double getStatistic(String name,String groupOrKey); void putStatistic(String name, Double value, String group, String scenario, String step); void putStatistic(String name,Double value, String group, String scenario); void putStatistic(String name,Double value,String groupOrKey); void putKey(String group, String scenario, String step); void putKey(String group, String scenario); void putKey(String groupOrKey); void addStatistics(Stats stats); boolean isEmpty(); static String SEP; }### Answer:
@Test public void testIsEmpty() { Stats stats = new Stats(); stats.putStatisticType(Stats.StatType.PASSED.type); stats.putStatisticType(Stats.StatType.FAILED.type); stats.putKey("grp","scn"); assertFalse(stats.isEmpty()); }