### Question:
TaskDifficultyComparator implements Comparator<Task>,
                                                 Serializable { @Override public int compare(Task a, Task b) { return COMPARATOR.compare(a, b); }  @Override int compare(Task a, Task b);  }### Answer:
@Test public void testCompare() { TaskDifficultyComparator comparator = new TaskDifficultyComparator(); testEquals(comparator, new Task(1, "name", 5), new Task(1, "name", 5)); testLessThan(comparator, new Task(1, "name", 5), new Task(1, "name", 1)); testGreaterThan(comparator, new Task(1, "name", 1), new Task(1, "name", 5)); testLessThan(comparator, new Task(1, "name", 5), new Task(2, "name", 5)); testGreaterThan(comparator, new Task(2, "name", 5), new Task(1, "name", 5)); }