com.hazelcast.cardinality.impl.hyperloglog.impl

Class HyperLogLogImpl

java.lang.Object

com.hazelcast.cardinality.impl.hyperloglog.impl.HyperLogLogImpl

All Implemented Interfaces:

HyperLogLog, DataSerializable, IdentifiedDataSerializable, Versioned

public class HyperLogLogImpl
extends Object
implements HyperLogLog, Versioned

Constructor Summary

Constructors

Constructor and Description
HyperLogLogImpl()
HyperLogLogImpl(int p)

Method Summary

Modifier and Type	Method and Description
void	add(long hash) Aggregates the hash in the HyperLogLog registers.
void	addAll(long[] hashes) Batch aggregation of hash values in the HyperLogLog registers.
long	estimate() Computes a new estimate for the current status of the registers.
int	getFactoryId() Returns DataSerializableFactory factory ID for this class.
int	getId() Returns type identifier for this class.
void	merge(HyperLogLog other) Merge the two HyperLogLog structures in one.
void	readData(ObjectDataInput in) Reads fields from the input stream
void	writeData(ObjectDataOutput out) Writes object fields to output stream

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

HyperLogLogImpl

public HyperLogLogImpl()

HyperLogLogImpl

public HyperLogLogImpl(int p)

Method Detail

estimate

public long estimate()

Description copied from interface: HyperLogLog

Computes a new estimate for the current status of the registers. If it was previously estimated and never invalidated, then a cached version is used.

Specified by:

estimate in interface HyperLogLog

Returns:

previously cached estimation or a newly computed one.

add

public void add(long hash)

Description copied from interface: HyperLogLog

Aggregates the hash in the HyperLogLog registers.

Specified by:

add in interface HyperLogLog

Parameters:

hash - the value to aggregate

addAll

public void addAll(long[] hashes)

Description copied from interface: HyperLogLog

Batch aggregation of hash values in the HyperLogLog registers.

Specified by:

addAll in interface HyperLogLog

Parameters:

hashes - the hash values array to aggregate

merge

public void merge(HyperLogLog other)

Description copied from interface: HyperLogLog

Merge the two HyperLogLog structures in one. Estimations from both are taken into consideration and the unified estimate should be similar to the distinct union set of the two.

Specified by:

merge in interface HyperLogLog

Parameters:

other - The second HLL to be merged into this one

getFactoryId

public int getFactoryId()

Description copied from interface: IdentifiedDataSerializable

Returns DataSerializableFactory factory ID for this class.

Specified by:

getFactoryId in interface IdentifiedDataSerializable

Returns:

factory ID

getId

public int getId()

Description copied from interface: IdentifiedDataSerializable

Returns type identifier for this class. It should be unique per DataSerializableFactory.

Specified by:

getId in interface IdentifiedDataSerializable

Returns:

type ID

writeData

public void writeData(ObjectDataOutput out)
               throws IOException

Description copied from interface: DataSerializable

Writes object fields to output stream

Specified by:

writeData in interface DataSerializable

Parameters:

out - output

Throws:

IOException - if an I/O error occurs. In particular, an IOException may be thrown if the output stream has been closed.

readData

public void readData(ObjectDataInput in)
              throws IOException

Description copied from interface: DataSerializable

Reads fields from the input stream

Specified by:

readData in interface DataSerializable

Parameters:

in - input

Throws:

IOException - if an I/O error occurs. In particular, an IOException may be thrown if the input stream has been closed.