static <E> Subgroup<E> smallSubgroup(final Group<E> group, final Group<E> subgroup) {
if (group == null) throw new IllegalArgumentException("null group");
if (subgroup == null) throw new IllegalArgumentException("null subgroup");
if (!group.getSize().isSmall()) throw new IllegalArgumentException("large group not supported");
if (!group.equality().equals(subgroup.equality()))
throw new IllegalArgumentException("equality differs between group and subgroup");
E id1 = group.op().identity();
E id2 = subgroup.op().identity();
if (!group.equality().isEquivalent(id1, id2))
throw new IllegalArgumentException("identity differs between group and subgroup");
return new SmallSubgroup<E>(group, subgroup);
}
@Override
@SuppressWarnings("unchecked")
protected AbstractGroup[][] prepareGroups() {
// Check
String valid = isValid();
if (valid != null) {
throw new IllegalArgumentException(valid);
}
// Create adjustments
Range<T>[] ranges = getAdjustedRanges();
Range<T> tempLower = ranges[0];
Range<T> tempUpper = ranges[1];
// Build leaf level index
ArrayList<IndexNode> nodes = new ArrayList<IndexNode>();
for (int i = 0, len = intervals.size(); i < len; i += INDEX_FANOUT) {
int min = i;
int max = Math.min(i + INDEX_FANOUT - 1, len - 1);
List<Interval<T>> leafs = new ArrayList<Interval<T>>();
for (int j = min; j <= max; j++) {
leafs.add(intervals.get(j));
}
nodes.add(
new IndexNode(
intervals.get(min).min,
intervals.get(max).max,
leafs.toArray(new Interval[leafs.size()])));
}
// Builder inner nodes
while (nodes.size() > 1) {
List<IndexNode> current = (List<IndexNode>) nodes.clone();
nodes.clear();
for (int i = 0, len = current.size(); i < len; i += INDEX_FANOUT) {
int min = i;
int max = Math.min(i + INDEX_FANOUT - 1, len - 1);
List<IndexNode> temp = new ArrayList<IndexNode>();
for (int j = min; j <= max; j++) {
temp.add(current.get(j));
}
nodes.add(
new IndexNode(
current.get(min).min,
current.get(max).max,
temp.toArray(new HierarchyBuilderIntervalBased.IndexNode[temp.size()])));
}
}
// Prepare
String[] data = getData();
List<AbstractGroup[]> result = new ArrayList<AbstractGroup[]>();
IndexNode index = nodes.get(0);
// Prepare
DataTypeWithRatioScale<T> type = (DataTypeWithRatioScale<T>) getDataType();
Map<AbstractGroup, AbstractGroup> cache = new HashMap<AbstractGroup, AbstractGroup>();
// Create snap intervals
Interval<T> lowerSnap = getInterval(index, type, tempLower.repeatBound);
lowerSnap =
new Interval<T>(
this, getDataType(), tempLower.snapBound, lowerSnap.max, lowerSnap.function);
Interval<T> upperSnap = getIntervalUpperSnap(index, type, tempUpper.repeatBound);
upperSnap =
new Interval<T>(
this, getDataType(), upperSnap.min, tempUpper.snapBound, upperSnap.function);
// Overlapping snaps -> one interval
if (type.compare(lowerSnap.max, upperSnap.min) > 0) {
// We could use lowerSnap.function or upperSnap.function
lowerSnap =
new Interval<T>(this, getDataType(), lowerSnap.min, upperSnap.max, lowerSnap.function);
upperSnap = lowerSnap;
}
// Create first column
AbstractGroup[] first = new AbstractGroup[data.length];
for (int i = 0; i < data.length; i++) {
T value = type.parse(data[i]);
Interval<T> interval;
if (value == null) {
interval = new Interval<T>(this);
} else if (type.compare(value, tempLower.labelBound) < 0) {
throw new IllegalArgumentException(type.format(value) + " is < lower label bound");
} else if (type.compare(value, tempLower.snapBound) < 0) {
interval = new Interval<T>(this, true, tempLower.snapBound);
} else if (type.compare(value, tempUpper.labelBound) >= 0) {
throw new IllegalArgumentException(type.format(value) + " is >= upper label bound");
} else if (type.compare(value, tempUpper.snapBound) >= 0) {
interval = new Interval<T>(this, false, tempUpper.snapBound);
} else {
interval = getInterval(index, type, value);
}
if (interval.min != null && interval.max != null) {
if (type.compare(interval.min, lowerSnap.max) < 0) {
interval = lowerSnap;
} else if (type.compare(interval.max, upperSnap.min) > 0) {
interval = upperSnap;
}
}
first[i] = getGroup(cache, interval);
}
result.add(first);
// Clean
index = null;
// Create other columns
List<Group<T>> groups = new ArrayList<Group<T>>();
if (!super.getLevels().isEmpty()) groups = super.getLevels().get(0).getGroups();
if (cache.size() > 1 && !groups.isEmpty()) {
// Prepare
List<Interval<T>> newIntervals = new ArrayList<Interval<T>>();
int intervalIndex = 0;
int multiplier = 0;
T width = type.subtract(intervals.get(intervals.size() - 1).max, intervals.get(0).min);
// Merge intervals
for (Group<T> group : groups) {
// Find min and max
T min = null;
T max = null;
for (int i = 0; i < group.getSize(); i++) {
Interval<T> current = intervals.get(intervalIndex++);
T offset = type.multiply(width, multiplier);
T cMin = type.add(current.min, offset);
T cMax = type.add(current.max, offset);
if (min == null || type.compare(min, cMin) > 0) {
min = cMin;
}
if (max == null || type.compare(max, cMax) < 0) {
max = cMax;
}
if (intervalIndex == intervals.size()) {
intervalIndex = 0;
multiplier++;
}
}
// Add interval
newIntervals.add(new Interval<T>(this, getDataType(), min, max, group.getFunction()));
}
// Compute next column
HierarchyBuilderIntervalBased<T> builder =
new HierarchyBuilderIntervalBased<T>(getDataType(), tempLower, tempUpper);
for (Interval<T> interval : newIntervals) {
builder.addInterval(interval.min, interval.max, interval.function);
}
for (int i = 1; i < super.getLevels().size(); i++) {
for (Group<T> sgroup : super.getLevel(i).getGroups()) {
builder.getLevel(i - 1).addGroup(sgroup.getSize(), sgroup.getFunction());
}
}
// Copy data
builder.prepare(data);
AbstractGroup[][] columns = builder.getPreparedGroups();
for (AbstractGroup[] column : columns) {
result.add(column);
}
} else {
if (cache.size() > 1) {
AbstractGroup[] column = new AbstractGroup[data.length];
@SuppressWarnings("serial")
AbstractGroup element = new AbstractGroup(DataType.ANY_VALUE) {};
for (int i = 0; i < column.length; i++) {
column[i] = element;
}
result.add(column);
}
}
// Return
return result.toArray(new AbstractGroup[0][0]);
}