@Override
public boolean remove(final Key key) {
if (key == null) throw new IllegalArgumentException("key cannot be null");
if (buckets != null) {
int hashCode = comparer.GetHashCode(key) & 0x7FFFFFFF;
int bucket = hashCode % buckets.length;
int last = -1;
for (int i = buckets[bucket]; i >= 0; last = i, i = entries[i].next) {
if (entries[i].hashCode == hashCode && comparer.Equals(entries[i].key, key)) {
if (last < 0) buckets[bucket] = entries[i].next;
else entries[last].next = entries[i].next;
entries[i].hashCode = -1;
entries[i].next = freeList;
entries[i].key = null;
entries[i].value = null;
freeList = i;
freeCount++;
version++;
return true;
}
}
}
return false;
}
private int findEntry(Key key) {
if (key == null) throw new IllegalArgumentException("key cannot be null");
if (buckets != null) {
int hashCode = comparer.GetHashCode(key) & 0x7FFFFFFF;
for (int i = buckets[hashCode % buckets.length]; i >= 0; i = entries[i].next) {
if (entries[i].hashCode == hashCode && comparer.Equals(entries[i].key, key)) return i;
}
}
return -1;
}
private void insert(Key key, Value value, boolean add) {
if (key == null) throw new IllegalArgumentException("key cannot be null");
if (buckets == null) initialize(0);
int hashCode = comparer.GetHashCode(key) & 0x7FFFFFFF;
int targetBucket = hashCode % buckets.length;
for (int i = buckets[targetBucket]; i >= 0; i = entries[i].next) {
if (entries[i].hashCode == hashCode && comparer.Equals(entries[i].key, key)) {
if (add) throw new IllegalArgumentException("Attempted to add items with duplicate keys");
entries[i].value = value;
version++;
return;
}
}
int index;
if (freeCount > 0) {
index = freeList;
freeList = entries[index].next;
freeCount--;
} else {
if (count == entries.length) {
Resize();
targetBucket = hashCode % buckets.length;
}
index = count;
count++;
}
entries[index].hashCode = hashCode;
entries[index].next = buckets[targetBucket];
entries[index].key = key;
entries[index].value = value;
buckets[targetBucket] = index;
version++;
}
private void Resize(int newSize, boolean forceNewHashCodes) {
// Contract.Assert(newSize >= entries.Length);
int[] newBuckets = new int[newSize];
for (int i = 0; i < newBuckets.length; i++) newBuckets[i] = -1;
Entry<Key, Value>[] newEntries = new Entry[newSize];
copy(entries, 0, newEntries, 0, count);
setNullsToDefault(newEntries);
if (forceNewHashCodes) {
for (int i = 0; i < count; i++) {
if (newEntries[i].hashCode != -1) {
newEntries[i].hashCode = (comparer.GetHashCode(newEntries[i].key) & 0x7FFFFFFF);
}
}
}
for (int i = 0; i < count; i++) {
if (newEntries[i].hashCode >= 0) {
int bucket = newEntries[i].hashCode % newSize;
newEntries[i].next = newBuckets[bucket];
newBuckets[bucket] = i;
}
}
buckets = newBuckets;
entries = newEntries;
}