/// <summary>
/// instanciate a new bloom filter with a the specified bit count
/// the maximum allowed bits for this implementation is 2^32.
/// a chunk of memory the size of bitCount is allocated imidiatly after calling this constructor.
/// </summary>
/// <param name="bitCount">the amount of bits used by this bloom filter. all memory is allocated imidiatly</param>
/// <param name="hashFunction">The hash function used by this bloom filter</param>
/// <param name="totalHashes">the number of hashes for each opertation in this filter. this value
/// must be lower than or equal to hashFunction.HashCount</param>
public ConcurrentBloomFilter(ulong bitCount, IKHashFunction <uint> hashFunction, int totalHashes)
{
if (hashFunction == null)
{
hashFunction = new RehashKHashFunction <uint>(new FNV1A32HashFunction()); // the default hash function is FNV1A
}
if (totalHashes > hashFunction.HashCount)
{
throw new IndexOutOfRangeException("totalHashes is to large for the provided hashFunction");
}
mHashes = totalHashes;
mHashFunction = hashFunction;
if (bitCount > uint.MaxValue)
{
throw new OutOfMemoryException("This implementation of bloom's filter is limited to a max of 2^32 bits");
}
mBitCount = (uint)bitCount;
uint dataSize = (mBitCount / BitsPerArrayItem) + 1;
mData = new int[dataSize];
}
/// <summary>
/// instanciate a new bloom filter with an intented capacity and with specified number of bits per element
/// the maximum allowed bits for this implementation is 2^32. so capacity*bitsPerElement must be under 2^32.
/// a chunk of memory the size of capacity*bitsPerElement is allocated imidiatly after calling this constructor.
/// </summary>
/// <param name="capacity">the intended amount of elements for this bloom filter. all memory is allocated imidiatly</param>
/// <param name="bitsPerElement">the number of bits for each element of this bloom filter</param>
/// <param name="hashFunction">The hash function used by this bloom filter</param>
/// <param name="totalHashes">the number of hashes for each opertation in this filter. this value
/// must be lower than or equal to hashFunction.HashCount</param>
public ConcurrentBloomFilter(int capacity, int bitsPerElement, IKHashFunction <uint> hashFunction, int totalHashes)
: this(((ulong)capacity) * ((ulong)bitsPerElement), hashFunction, totalHashes)
{
}