List listOfStrings = Arrays.asList("A", "B", "C", "A", "B");
@Test
public void testSumFunction() throws Exception {
AggregateFunction sf = aggregateFunctionManager.getFunctionByCode(SumFunction.CODE);
double result = sf.aggregate(listOfNumbers);
assertThat(result).isEqualTo(15);
}
@Test
public void testAvgFunction() throws Exception {