Package org.apache.druid.math.expr

Class LambdaExpr

java.lang.Object

org.apache.druid.math.expr.LambdaExpr

All Implemented Interfaces:

Cacheable, Expr

public class LambdaExpr
extends Object
implements Expr

Nested Class Summary

Nested classes/interfaces inherited from interface org.apache.druid.math.expr.Expr

Expr.BindingAnalysis, Expr.InputBindingInspector, Expr.ObjectBinding, Expr.Shuttle, Expr.VectorInputBinding, Expr.VectorInputBindingInspector

Field Summary

Fields inherited from interface org.apache.druid.math.expr.Expr

ARG_JOINER, NULL_LITERAL

Method Summary

Modifier and Type	Method	Description
Expr.BindingAnalysis	analyzeInputs()	Examine the usage of IdentifierExpr children of an Expr, constructing a Expr.BindingAnalysis
<T> ExprVectorProcessor<T>	asVectorProcessor(Expr.VectorInputBindingInspector inspector)	Builds a 'vectorized' expression processor, that can operate on batches of input values for use in vectorized query engines.
boolean	canVectorize(Expr.InputBindingInspector inspector)	Check if an expression can be 'vectorized', for a given set of inputs.
boolean	equals(Object o)
ExprEval	eval(Expr.ObjectBinding bindings)	Evaluate the Expr with the bindings which supply IdentifierExpr with their values, producing an ExprEval with the result.
Expr	getExpr()
String	getIdentifier()
List<String>	getIdentifiers()
ExpressionType	getOutputType(Expr.InputBindingInspector inspector)	Given an Expr.InputBindingInspector, compute what the output ExpressionType will be for this expression.
int	hashCode()
String	stringify()	Convert the Expr back into parseable string that when parsed with Parser.parse(String, ExprMacroTable) will produce an equivalent Expr.
List<String>	stringifyIdentifiers()
String	toString()
Expr	visit(Expr.Shuttle shuttle)	Programatically rewrite the Expr tree with a Expr.Shuttle.

Methods inherited from class java.lang.Object

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

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

asBitmapColumnIndex, asColumnIndexSupplier, asSingleThreaded, decorateCacheKeyBuilder, getBindingIfIdentifier, getCacheKey, getIdentifierExprIfIdentifierExpr, getIdentifierIfIdentifier, getLiteralValue, isIdentifier, isLiteral, isNullLiteral

Method Details

toString

public String toString()

Overrides:

toString in class Object

getIdentifier

@Nullable
public String getIdentifier()

getIdentifiers

public List<String> getIdentifiers()

stringifyIdentifiers

public List<String> stringifyIdentifiers()

getExpr

public Expr getExpr()

canVectorize

public boolean canVectorize(Expr.InputBindingInspector inspector)

Description copied from interface: Expr

Check if an expression can be 'vectorized', for a given set of inputs. If this method returns true, Expr.asVectorProcessor(org.apache.druid.math.expr.Expr.VectorInputBindingInspector) is expected to produce a ExprVectorProcessor which can evaluate values in batches to use with vectorized query engines.

Specified by:

canVectorize in interface Expr

Parameters:

inspector -

asVectorProcessor

public <T> ExprVectorProcessor<T> asVectorProcessor(Expr.VectorInputBindingInspector inspector)

Description copied from interface: Expr

Builds a 'vectorized' expression processor, that can operate on batches of input values for use in vectorized query engines.

Specified by:

asVectorProcessor in interface Expr

Parameters:

inspector -

eval

public ExprEval eval(Expr.ObjectBinding bindings)

Description copied from interface: Expr

Evaluate the Expr with the bindings which supply IdentifierExpr with their values, producing an ExprEval with the result.

Specified by:

eval in interface Expr

stringify

public String stringify()

Description copied from interface: Expr

Convert the Expr back into parseable string that when parsed with Parser.parse(String, ExprMacroTable) will produce an equivalent Expr.

Specified by:

stringify in interface Expr

visit

public Expr visit(Expr.Shuttle shuttle)

Description copied from interface: Expr

Programatically rewrite the Expr tree with a Expr.Shuttle. Each Expr is responsible for ensuring the Expr.Shuttle can visit all of its Expr children, as well as updating its children Expr with the results from the Expr.Shuttle, before finally visiting an updated form of itself. When this Expr is the result of ExprMacroTable.ExprMacro.apply(java.util.List<org.apache.druid.math.expr.Expr>), all of the original arguments to the macro must be visited, including arguments that may have been "baked in" to this Expr.

Specified by:

visit in interface Expr

analyzeInputs

public Expr.BindingAnalysis analyzeInputs()

Description copied from interface: Expr

Examine the usage of IdentifierExpr children of an Expr, constructing a Expr.BindingAnalysis

Specified by:

analyzeInputs in interface Expr

getOutputType

public ExpressionType getOutputType(Expr.InputBindingInspector inspector)

Description copied from interface: Expr

Given an Expr.InputBindingInspector, compute what the output ExpressionType will be for this expression. In the vectorized expression engine, if Expr.canVectorize(InputBindingInspector) returns true, a return value of null MUST ONLY indicate that the expression has all null inputs (non-existent columns) or null constants for the entire expression. Otherwise, all vectorizable expressions must produce an output type to correctly operate with the vectorized engine. Outside the context of vectorized expressions, a return value of null can also indicate that the given type information was not enough to resolve the output type, so the expression must be evaluated using default Expr.eval(org.apache.druid.math.expr.Expr.ObjectBinding) handling where types are only known after evaluation, through ExprEval.type(), such as transform expressions at ingestion time

Specified by:

getOutputType in interface Expr

equals

public boolean equals(Object o)

Overrides:

equals in class Object

hashCode

public int hashCode()

Overrides:

hashCode in class Object