/** Collects all the StarTree leaves that match the provided dimension values */
private void findMatchingLeaves(
StarTreeIndexNode node, List<Integer> values, Set<StarTreeIndexNode> leaves) {
if (node.isLeaf()) {
leaves.add(node);
} else {
Integer value = values.get(node.getChildDimensionName());
findMatchingLeaves(node.getChildren().get(value), values, leaves);
findMatchingLeaves(node.getChildren().get(StarTreeIndexNode.all()), values, leaves);
}
}
/**
* Returns the unique metric values for each column.
*
* <p>The original unique values cannot be used because after aggregation, we almost certainly
* have new values to encode that were not present in the original data set.
*/
private Map<String, Set<Object>> computeUniqueMetricValues() {
Map<String, Set<Object>> uniqueMetricValues = new HashMap<String, Set<Object>>();
Iterator<StarTreeTableRow> tableIterator = starTreeBuilder.getTable().getAllCombinations();
while (tableIterator.hasNext()) {
StarTreeTableRow row = tableIterator.next();
for (int i = 0; i < schema.getMetricNames().size(); i++) {
String metricName = schema.getMetricNames().get(i);
Object metricValue = row.getMetrics().get(i);
Set<Object> uniqueValues = uniqueMetricValues.get(metricName);
if (uniqueValues == null) {
uniqueValues = new HashSet<Object>();
uniqueMetricValues.put(metricName, uniqueValues);
}
uniqueValues.add(metricValue);
}
}
return uniqueMetricValues;
}