io.crate.expression.symbol

Class Function

java.lang.Object

io.crate.expression.symbol.Symbol

io.crate.expression.symbol.Function

All Implemented Interfaces:

FuncArg, ExplainLeaf, java.lang.Cloneable, org.elasticsearch.common.io.stream.Writeable

public class Function
extends Symbol
implements java.lang.Cloneable

Nested Class Summary

Nested classes/interfaces inherited from interface org.elasticsearch.common.io.stream.Writeable

org.elasticsearch.common.io.stream.Writeable.Reader<V>, org.elasticsearch.common.io.stream.Writeable.Writer<V>

Constructor Summary

Constructors

Constructor and Description
Function(FunctionInfo info, java.util.List<Symbol> arguments)
Function(org.elasticsearch.common.io.stream.StreamInput in)

Method Summary

Modifier and Type	Method and Description
<C,R> R	accept(SymbolVisitor<C,R> visitor, C context)
java.util.List<Symbol>	arguments()
boolean	canBeCasted() We only allow casting of Literal, Function, ParameterSymbol, and Symbols whose type is undefined.
Symbol	cast(DataType newDataType, boolean tryCast) Casts this Symbol to a new DataType by wrapping a cast function around it.
boolean	equals(java.lang.Object o)
int	hashCode()
FunctionInfo	info()
boolean	isValueSymbol() Returns true if this Symbol holds a value that may be cast preferably before other Symbols, ie.
java.lang.String	representation()
SymbolType	symbolType()
DataType	valueType() Returns the DataType of this Function argument.
void	writeTo(org.elasticsearch.common.io.stream.StreamOutput out)

Methods inherited from class io.crate.expression.symbol.Symbol

cast, isLiteral, toString

Methods inherited from class java.lang.Object

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

Methods inherited from interface io.crate.planner.ExplainLeaf

printList

Constructor Detail

Function

public Function(org.elasticsearch.common.io.stream.StreamInput in)
         throws java.io.IOException

Throws:

java.io.IOException

Function

public Function(FunctionInfo info,
                java.util.List<Symbol> arguments)

Method Detail

arguments

public java.util.List<Symbol> arguments()

info

public FunctionInfo info()

valueType

public DataType valueType()

Description copied from interface: FuncArg

Returns the DataType of this Function argument.

Specified by:

valueType in interface FuncArg

Specified by:

valueType in class Symbol

Returns:

The DataType of the value.

canBeCasted

public boolean canBeCasted()

Description copied from class: Symbol

We only allow casting of Literal, Function, ParameterSymbol, and Symbols whose type is undefined. The reasoning behind this is that we want to avoid query Lucene performance to drop due to casts. This is true for Field/Reference.

Specified by:

canBeCasted in interface FuncArg

Overrides:

canBeCasted in class Symbol

Returns:

True is casting is possible, false otherwise.

isValueSymbol

public boolean isValueSymbol()

Description copied from interface: FuncArg

Returns true if this Symbol holds a value that may be cast preferably before other Symbols, ie. Literal and ParameterSymbols.

Specified by:

isValueSymbol in interface FuncArg

Returns:

True if it is a value symbol, False otherwise

cast

public Symbol cast(DataType newDataType,
                   boolean tryCast)

Description copied from class: Symbol

Casts this Symbol to a new DataType by wrapping a cast function around it. Sublasses of this class may provide another cast methods.

Overrides:

cast in class Symbol

Parameters:

newDataType - The resulting data type after applying the cast

tryCast - If set to true, will return null the symbol cannot be casted.

Returns:

An instance of Function which casts this symbol.

symbolType

public SymbolType symbolType()

Specified by:

symbolType in class Symbol

accept

public <C,R> R accept(SymbolVisitor<C,R> visitor,
                      C context)

Specified by:

accept in class Symbol

writeTo

public void writeTo(org.elasticsearch.common.io.stream.StreamOutput out)
             throws java.io.IOException

Specified by:

writeTo in interface org.elasticsearch.common.io.stream.Writeable

Throws:

java.io.IOException

representation

public java.lang.String representation()

Specified by:

representation in interface ExplainLeaf

Returns:

Human readable representation of the component

equals

public boolean equals(java.lang.Object o)

Overrides:

equals in class java.lang.Object

hashCode

public int hashCode()

Overrides:

hashCode in class java.lang.Object