static void
_parcHashMap_Resize(PARCHashMap *hashMap, size_t newCapacity)
{
if (newCapacity < hashMap->minCapacity) {
return;
}
PARCLinkedList **newBuckets = parcMemory_AllocateAndClear(newCapacity * sizeof(PARCLinkedList*));
for (unsigned int i = 0; i < hashMap->capacity; i++) {
if (hashMap->buckets[i] != NULL) {
if (!parcLinkedList_IsEmpty(hashMap->buckets[i])) {
PARCIterator *elementIt = parcLinkedList_CreateIterator(hashMap->buckets[i]);
while (parcIterator_HasNext(elementIt)) {
_PARCHashMapEntry *entry = parcIterator_Next(elementIt);
PARCHashCode keyHash = parcObject_HashCode(entry->key);
int newBucket = keyHash % newCapacity;
if (newBuckets[newBucket] == NULL) {
newBuckets[newBucket] = parcLinkedList_Create();
}
parcLinkedList_Append(newBuckets[newBucket], entry);
}
parcIterator_Release(&elementIt);
}
parcLinkedList_Release(&hashMap->buckets[i]);
}
}
PARCLinkedList **cleanupBuckets = hashMap->buckets;
hashMap->buckets = newBuckets;
hashMap->capacity = newCapacity;
parcMemory_Deallocate(&cleanupBuckets);
}
bool
parcHashMap_Remove(PARCHashMap *hashMap, const PARCObject *key)
{
PARCHashCode keyHash = parcObject_HashCode(key);
int bucket = keyHash % hashMap->capacity;
bool result = false;
if (hashMap->buckets[bucket] != NULL) {
PARCIterator *iterator = parcLinkedList_CreateIterator(hashMap->buckets[bucket]);
while (parcIterator_HasNext(iterator)) {
_PARCHashMapEntry *entry = parcIterator_Next(iterator);
if (parcObject_Equals(key, entry->key)) {
parcIterator_Remove(iterator);
hashMap->size--;
result = true;
break;
}
}
parcIterator_Release(&iterator);
}
// When expanded by 2 the load factor goes from .75 (3/4) to .375 (3/8), if
// we compress by 2 when the load factor is .25 (1/4) the load
// factor becomes .5 (1/2).
double loadFactor = (double)hashMap->size/(double)hashMap->capacity;
if (loadFactor <= (hashMap->minLoadFactor)) {
_parcHashMap_Resize(hashMap, hashMap->capacity / 2);
}
return result;
}
static _PARCHashMapEntry *
_parcHashMap_GetEntry(const PARCHashMap *hashMap, const PARCObject *key)
{
PARCHashCode keyHash = parcObject_HashCode(key);
int bucket = keyHash % hashMap->capacity;
_PARCHashMapEntry *result = NULL;
if (hashMap->buckets[bucket] != NULL) {
PARCIterator *iterator = parcLinkedList_CreateIterator(hashMap->buckets[bucket]);
while (parcIterator_HasNext(iterator)) {
_PARCHashMapEntry *entry = parcIterator_Next(iterator);
if (parcObject_Equals(key, entry->key)) {
result = entry;
break;
}
}
parcIterator_Release(&iterator);
}
return result;
}
PARCIterator *
parcSortedList_CreateIterator(PARCSortedList *instance)
{
return parcLinkedList_CreateIterator(instance->list);
}
