package org.apache.cassandra.utils;
/*
*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*
*/
import java.io.DataInput;
import java.io.DataOutput;
import java.io.IOException;
import org.apache.cassandra.db.DBConstants;
import org.apache.cassandra.io.ICompactSerializer2;
import org.apache.cassandra.utils.obs.OpenBitSet;
class BloomFilterSerializer implements ICompactSerializer2<BloomFilter>
{
public void serialize(BloomFilter bf, DataOutput dos) throws IOException
{
long[] bits = bf.bitset.getBits();
int bitLength = bits.length;
dos.writeInt(bf.getHashCount());
dos.writeInt(bitLength);
for (int i = 0; i < bitLength; i++)
dos.writeLong(bits[i]);
}
public BloomFilter deserialize(DataInput dis) throws IOException
{
int hashes = dis.readInt();
int bitLength = dis.readInt();
long[] bits = new long[bitLength];
for (int i = 0; i < bitLength; i++)
bits[i] = dis.readLong();
OpenBitSet bs = new OpenBitSet(bits, bitLength);
return new BloomFilter(hashes, bs);
}
/**
* Calculates a serialized size of the given Bloom Filter
* @see this.serialize(BloomFilter, DataOutput)
*
* @param bf Bloom filter to calculate serialized size
*
* @return serialized size of the given bloom filter
*/
public static int serializedSize(BloomFilter bf)
{
return DBConstants.intSize // hash count
+ DBConstants.intSize // length
+ bf.bitset.getBits().length * DBConstants.longSize; // buckets
}
}