public Calculation(final C[] catagories, final Operation... operations) {
if (catagories == null) {
throw new NullPointerException("categories.not.specified");
}
if (operations == null || operations.length == 0) {
throw new NullPointerException("operations.not.specified");
}
this.catagories = Arrays.copyOf(catagories, catagories.length);
for (final Operation operation : operations) {
this.operations[operation.ordinal()] = operation;
}
if (this.operations[Operation.SUM.ordinal()] != null
|| this.operations[Operation.AVERAGE.ordinal()] != null) {
sum = new BigDecimal[catagories.length];
final BigDecimal zero = new BigDecimal(0);
for (int i = 0; i < catagories.length; i++) {
sum[i] = zero;
}
}
if (this.operations[Operation.AVERAGE.ordinal()] != null) {
count = new long[catagories.length];
}
if (this.operations[Operation.MEDIAN.ordinal()] != null) {
values = new List[catagories.length];
for (int i = 0; i < catagories.length; i++) {
values[i] = new ArrayList<BigDecimal>();
}
}
}
public void registerValue(final C catagory, final BigDecimal value) {
final int index = getIndex(catagory);
if (operations[Operation.AVERAGE.ordinal()] != null) {
count[index]++;
sum[index] = sum[index].add(value);
} else if (operations[Operation.SUM.ordinal()] != null) {
sum[index] = sum[index].add(value);
}
if (operations[Operation.MEDIAN.ordinal()] != null) {
values[index].add(value);
}
}
