Package org.apache.flink.api.common.accumulators

Class Histogram

java.lang.Object

org.apache.flink.api.common.accumulators.Histogram

All Implemented Interfaces:

Serializable, Cloneable, Accumulator<Integer,TreeMap<Integer,Integer>>

@Public
public class Histogram
extends Object
implements Accumulator<Integer,TreeMap<Integer,Integer>>

Histogram accumulator, which builds a histogram in a distributed manner. Implemented as a Integer->Integer TreeMap, so that the entries are sorted according to the values.

This class does not extend to continuous values later, because it makes no attempt to put the data in bins.

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor	Description
Histogram()

Method Summary

Modifier and Type	Method	Description
void	add(Integer value)
Accumulator<Integer,TreeMap<Integer,Integer>>	clone()	Duplicates the accumulator.
TreeMap<Integer,Integer>	getLocalValue()
void	merge(Accumulator<Integer,TreeMap<Integer,Integer>> other)	Used by system internally to merge the collected parts of an accumulator at the end of the job.
void	resetLocal()	Reset the local value.
String	toString()

Methods inherited from class java.lang.Object

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

Constructor Detail

Histogram

public Histogram()

Method Detail

add

public void add(Integer value)

Specified by:

add in interface Accumulator<Integer,TreeMap<Integer,Integer>>

Parameters:

value - The value to add to the accumulator object

getLocalValue

public TreeMap<Integer,Integer> getLocalValue()

Specified by:

getLocalValue in interface Accumulator<Integer,TreeMap<Integer,Integer>>

Returns:

local The local value from the current UDF context

merge

public void merge(Accumulator<Integer,TreeMap<Integer,Integer>> other)

Description copied from interface: Accumulator

Used by system internally to merge the collected parts of an accumulator at the end of the job.

Specified by:

merge in interface Accumulator<Integer,TreeMap<Integer,Integer>>

Parameters:

other - Reference to accumulator to merge in.

resetLocal

public void resetLocal()

Description copied from interface: Accumulator

Reset the local value. This only affects the current UDF context.

Specified by:

resetLocal in interface Accumulator<Integer,TreeMap<Integer,Integer>>

toString

public String toString()

Overrides:

toString in class Object

clone

public Accumulator<Integer,TreeMap<Integer,Integer>> clone()

Description copied from interface: Accumulator

Duplicates the accumulator. All subclasses need to properly implement cloning and cannot throw a CloneNotSupportedException

Specified by:

clone in interface Accumulator<Integer,TreeMap<Integer,Integer>>

Overrides:

clone in class Object

Returns:

The duplicated accumulator.