io.druid.query.aggregation.variance

Class VarianceBufferAggregator

java.lang.Object

io.druid.query.aggregation.variance.VarianceBufferAggregator

All Implemented Interfaces:

BufferAggregator

Direct Known Subclasses:

VarianceBufferAggregator.FloatVarianceAggregator, VarianceBufferAggregator.LongVarianceAggregator, VarianceBufferAggregator.ObjectVarianceAggregator

public abstract class VarianceBufferAggregator
extends Object
implements BufferAggregator

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	VarianceBufferAggregator.FloatVarianceAggregator
static class	VarianceBufferAggregator.LongVarianceAggregator
static class	VarianceBufferAggregator.ObjectVarianceAggregator

Field Summary

Fields

Modifier and Type	Field and Description
protected String	name

Constructor Summary

Constructors

Constructor and Description
VarianceBufferAggregator(String name)

Method Summary

Modifier and Type	Method and Description
void	close() Release any resources used by the aggregator
Object	get(ByteBuffer buf, int position) Returns the intermediate object representation of the given aggregate.
float	getFloat(ByteBuffer buf, int position) Returns the float representation of the given aggregate byte array Converts the given byte buffer representation into the intermediate aggregate value.
long	getLong(ByteBuffer buf, int position) Returns the long representation of the given aggregate byte array Converts the given byte buffer representation into the intermediate aggregate value.
void	init(ByteBuffer buf, int position) Initializes the buffer location Implementations of this method must initialize the byte buffer at the given position Implementations must not change the position, limit or mark of the given buffer This method must not exceed the number of bytes returned by AggregatorFactory.getMaxIntermediateSize() in the corresponding AggregatorFactory

Methods inherited from class java.lang.Object

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

Methods inherited from interface io.druid.query.aggregation.BufferAggregator

aggregate, relocate

Field Detail

name

protected final String name

Constructor Detail

VarianceBufferAggregator

public VarianceBufferAggregator(String name)

Method Detail

init

public void init(ByteBuffer buf,
                 int position)

Description copied from interface: BufferAggregator

Initializes the buffer location Implementations of this method must initialize the byte buffer at the given position Implementations must not change the position, limit or mark of the given buffer This method must not exceed the number of bytes returned by AggregatorFactory.getMaxIntermediateSize() in the corresponding AggregatorFactory

Specified by:

init in interface BufferAggregator

Parameters:

buf - byte buffer to initialize

position - offset within the byte buffer for initialization

get

public Object get(ByteBuffer buf,
                  int position)

Description copied from interface: BufferAggregator

Returns the intermediate object representation of the given aggregate. Converts the given byte buffer representation into an intermediate aggregate Object Implementations must not change the position, limit or mark of the given buffer

Specified by:

get in interface BufferAggregator

Parameters:

buf - byte buffer storing the byte array representation of the aggregate

position - offset within the byte buffer at which the aggregate value is stored

Returns:

the Object representation of the aggregate

getFloat

public float getFloat(ByteBuffer buf,
                      int position)

Description copied from interface: BufferAggregator

Returns the float representation of the given aggregate byte array Converts the given byte buffer representation into the intermediate aggregate value. Implementations must not change the position, limit or mark of the given buffer Implementations are only required to support this method if they are aggregations which have an AggregatorFactory.getTypeName() of "float". If unimplemented, throwing an UnsupportedOperationException is common and recommended.

Specified by:

getFloat in interface BufferAggregator

Parameters:

buf - byte buffer storing the byte array representation of the aggregate

position - offset within the byte buffer at which the aggregate value is stored

Returns:

the float representation of the aggregate

getLong

public long getLong(ByteBuffer buf,
                    int position)

Description copied from interface: BufferAggregator

Returns the long representation of the given aggregate byte array Converts the given byte buffer representation into the intermediate aggregate value. Implementations must not change the position, limit or mark of the given buffer Implementations are only required to support this method if they are aggregations which have an AggregatorFactory.getTypeName() of "long". If unimplemented, throwing an UnsupportedOperationException is common and recommended.

Specified by:

getLong in interface BufferAggregator

Parameters:

buf - byte buffer storing the byte array representation of the aggregate

position - offset within the byte buffer at which the aggregate value is stored

Returns:

the long representation of the aggregate

close

public void close()

Description copied from interface: BufferAggregator

Release any resources used by the aggregator

Specified by:

close in interface BufferAggregator