Package org.apache.druid.query.aggregation

Class ExpressionLambdaAggregatorInputBindings

java.lang.Object

org.apache.druid.query.aggregation.ExpressionLambdaAggregatorInputBindings

All Implemented Interfaces:

Expr.InputBindingInspector, Expr.ObjectBinding

public class ExpressionLambdaAggregatorInputBindings
extends Object
implements Expr.ObjectBinding

Special Expr.ObjectBinding for use with ExpressionLambdaAggregatorFactory. This value binding holds a value for a special 'accumulator' variable, in addition to the 'normal' bindings to the underlying selector inputs for other identifiers, which allows for easy forward feeding of the results of an expression evaluation to use in the bindings of the next evaluation.

Constructor Summary

Constructors

Constructor	Description
ExpressionLambdaAggregatorInputBindings(Expr.ObjectBinding inputBindings, String accumulatorIdentifier, ExprEval<?> initialValue)

Method Summary

Modifier and Type	Method	Description
void	accumulate(ExprEval<?> eval)
Object	get(String name)	Get value binding for string identifier of IdentifierExpr
ExprEval<?>	getAccumulator()
ExpressionType	getType(String name)	Get the ExpressionType from the backing store for a given identifier (this is likely a column, but could be other things depending on the backing adapter)
void	setAccumulator(ExprEval<?> acc)

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.druid.math.expr.Expr.InputBindingInspector

areNumeric, areNumeric, areSameTypes, areSameTypes, areScalar, areScalar, canVectorize, canVectorize

Constructor Detail

ExpressionLambdaAggregatorInputBindings

public ExpressionLambdaAggregatorInputBindings(Expr.ObjectBinding inputBindings,
                                               String accumulatorIdentifier,
                                               ExprEval<?> initialValue)

Method Detail

get

@Nullable
public Object get(String name)

Description copied from interface: Expr.ObjectBinding

Get value binding for string identifier of IdentifierExpr

Specified by:

get in interface Expr.ObjectBinding

getType

@Nullable
public ExpressionType getType(String name)

Description copied from interface: Expr.InputBindingInspector

Get the ExpressionType from the backing store for a given identifier (this is likely a column, but could be other things depending on the backing adapter)

Specified by:

getType in interface Expr.InputBindingInspector

accumulate

public void accumulate(ExprEval<?> eval)

getAccumulator

public ExprEval<?> getAccumulator()

setAccumulator

public void setAccumulator(ExprEval<?> acc)