/**
* Performs a binary search for {@code value} in the ascending sorted off-heap struct collection
* using int struct key. in the range specified by fromIndex (inclusive) and toIndex (exclusive).
* Searching in an unsorted collection has an undefined result. It's also undefined which element
* is found if there are multiple occurrences of the same element.
*
* @param collection the sorted collection to search.
* @param startIndex the inclusive start index.
* @param endIndex the exclusive end index.
* @param value the element to find.
* @param keyOffset int key field offset within stuct bounds
* @return the non-negative index of the element, or a negative index which is {@code -index - 1}
* where the element would be inserted.
* @throws IllegalArgumentException {@code if (startIndex < 0 || startIndex > endIndex || endIndex
* > collection.size()}
*/
public static long binarySearchByIntKey(
OffHeapStructCollection collection,
long startIndex,
long endIndex,
long value,
int keyOffset) {
if (startIndex < 0 || startIndex > endIndex || endIndex > collection.size()) {
throw new IllegalArgumentException(
"Illegal input, collection size: ["
+ collection.size()
+ "], "
+ "startIndex: ["
+ startIndex
+ "], endIndex: ["
+ endIndex
+ "]");
}
long lo = startIndex;
long hi = endIndex - 1;
while (lo <= hi) {
long mid = (lo + hi) >>> 1;
long midVal = collection.getInt(mid, keyOffset);
if (midVal < value) {
lo = mid + 1;
} else if (midVal > value) {
hi = mid - 1;
} else {
return mid; // value found
}
}
return ~lo; // value not present
}
/**
* Performs a binary search for {@code value} in the ascending sorted off-heap struct collection
* using int struct key. Returns range of indices having given value or empty range. Searching in
* an unsorted collection has an undefined result. It's also undefined which element is found if
* there are multiple occurrences of the same element.
*
* @param collection the sorted array to search.
* @param startIndex the inclusive start index.
* @param endIndex the exclusive end index.
* @param value the element to find.
* @param keyOffset int key field offset within stuct bounds
* @param out range instance, will be set with start/end indices having given value or with empty
* value
*/
public static void binarySearchRangeByIntKey(
OffHeapStructCollection collection,
long startIndex,
long endIndex,
long value,
int keyOffset,
IndexRange out) {
long ind = binarySearchByIntKey(collection, startIndex, endIndex, value, keyOffset);
if (ind < 0) {
out.setEmpty(ind);
return;
}
long from = ind;
while (from >= startIndex && value == collection.getInt(from, keyOffset)) {
from -= 1;
}
from += 1;
long to = ind;
while (to < endIndex && value == collection.getInt(to, keyOffset)) {
to += 1;
}
to -= 1;
out.set(from, to);
}