Package com.yahoo.searchlib.aggregation

Class AggregationResult

java.lang.Object

com.yahoo.vespa.objects.Selectable

com.yahoo.vespa.objects.Identifiable

com.yahoo.searchlib.expression.ExpressionNode

com.yahoo.searchlib.aggregation.AggregationResult

All Implemented Interfaces:

Serializable, Cloneable

Direct Known Subclasses:

AverageAggregationResult, CountAggregationResult, ExpressionCountAggregationResult, HitsAggregationResult, MaxAggregationResult, MinAggregationResult, StandardDeviationAggregationResult, SumAggregationResult, XorAggregationResult

public abstract class AggregationResult
extends ExpressionNode

The result of some aggregation

Author:

baldersheim, Simon Thoresen Hult

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field	Description
static int	classId

Constructor Summary

Constructors

Constructor	Description
AggregationResult()

Method Summary

Modifier and Type	Method	Description
AggregationResult	clone()
protected abstract boolean	equalsAggregation(AggregationResult obj)
protected boolean	equalsExpression(ExpressionNode obj)
ExpressionNode	getExpression()	Returns the expression to aggregate on.
abstract ResultNode	getRank()	Returns a value that can be used for ranking.
ResultNode	getResult()	Get the result of this expression.
int	getTag()	Returns the tag of this aggregation result.
void	merge(AggregationResult result)	Called when merging aggregation results.
protected void	onDeserialize(com.yahoo.vespa.objects.Deserializer buf)
boolean	onExecute()
protected int	onGetClassId()
protected abstract void	onMerge(AggregationResult result)	Mmust be implemented by subclasses to support merge.
void	onPrepare()
protected void	onSerialize(com.yahoo.vespa.objects.Serializer buf)
void	postMerge()	Hook called when all aggregation results have been merged.
AggregationResult	setExpression(ExpressionNode exp)	Sets the expression to aggregate on.
AggregationResult	setTag(int tag)	Assigns a tag to this group.
void	visitMembers(com.yahoo.vespa.objects.ObjectVisitor visitor)

Methods inherited from class com.yahoo.searchlib.expression.ExpressionNode

equals, execute, executeIterative, onArgument, prepare

Methods inherited from class com.yahoo.vespa.objects.Identifiable

create, createFromId, deserialize, deserializeOptional, deserializeWithId, equals, getClassId, getRawUtf8Bytes, getUtf8, hashCode, putUtf8, registerClass, serialize, serializeOptional, serializeWithId, toString

Methods inherited from class com.yahoo.vespa.objects.Selectable

select, select, selectMembers

Methods inherited from class java.lang.Object

finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

classId

public static final int classId

Constructor Detail

AggregationResult

public AggregationResult()

Method Detail

getTag

public int getTag()

Returns the tag of this aggregation result. This is useful for uniquely identifying a result.

Returns:

The numerical tag.

setTag

public AggregationResult setTag(int tag)

Assigns a tag to this group.

Parameters:

tag - the numerical tag to set.

Returns:

this, to allow chaining.

merge

public void merge(AggregationResult result)

Called when merging aggregation results. This method is simply a proxy for the abstract onMerge(AggregationResult) method.

Parameters:

result - the result to merge with.

postMerge

public void postMerge()

Hook called when all aggregation results have been merged. This method can be overloaded by subclasses that need special behaviour to occur after merge.

getRank

public abstract ResultNode getRank()

Returns a value that can be used for ranking.

setExpression

public AggregationResult setExpression(ExpressionNode exp)

Sets the expression to aggregate on.

Parameters:

exp - the expression

Returns:

this, to allow chaining

getExpression

public ExpressionNode getExpression()

Returns the expression to aggregate on.

onMerge

protected abstract void onMerge(AggregationResult result)

Mmust be implemented by subclasses to support merge. It is called as the merge(AggregationResult) method is invoked.

Parameters:

result - the result to merge with

getResult

public ResultNode getResult()

Description copied from class: ExpressionNode

Get the result of this expression.

Specified by:

getResult in class ExpressionNode

Returns:

the result as a ResultNode.

onPrepare

public void onPrepare()

Overrides:

onPrepare in class ExpressionNode

onExecute

public boolean onExecute()

Overrides:

onExecute in class ExpressionNode

onGetClassId

protected int onGetClassId()

Overrides:

onGetClassId in class ExpressionNode

onSerialize

protected void onSerialize(com.yahoo.vespa.objects.Serializer buf)

Overrides:

onSerialize in class ExpressionNode

onDeserialize

protected void onDeserialize(com.yahoo.vespa.objects.Deserializer buf)

Overrides:

onDeserialize in class ExpressionNode

clone

public AggregationResult clone()

Overrides:

clone in class ExpressionNode

equalsExpression

protected final boolean equalsExpression(ExpressionNode obj)

Specified by:

equalsExpression in class ExpressionNode

equalsAggregation

protected abstract boolean equalsAggregation(AggregationResult obj)

visitMembers

public void visitMembers(com.yahoo.vespa.objects.ObjectVisitor visitor)

Overrides:

visitMembers in class ExpressionNode