@Internal public final class ScalarFunctionDefinition extends Object implements FunctionDefinition
This class can be dropped once we introduce a new type inference.
Constructor and Description |
---|
ScalarFunctionDefinition(String name,
ScalarFunction scalarFunction) |
Modifier and Type | Method and Description |
---|---|
boolean |
equals(Object o) |
FunctionKind |
getKind()
Returns the kind of function this definition describes.
|
String |
getName() |
Set<FunctionRequirement> |
getRequirements()
Returns the set of requirements this definition demands.
|
ScalarFunction |
getScalarFunction() |
TypeInference |
getTypeInference(DataTypeFactory factory)
Returns the logic for performing type inference of a call to this function definition.
|
int |
hashCode() |
boolean |
isDeterministic()
Returns information about the determinism of the function's results.
|
String |
toString() |
public ScalarFunctionDefinition(String name, ScalarFunction scalarFunction)
public String getName()
public ScalarFunction getScalarFunction()
public FunctionKind getKind()
FunctionDefinition
getKind
in interface FunctionDefinition
public TypeInference getTypeInference(DataTypeFactory factory)
FunctionDefinition
The type inference process is responsible for inferring unknown types of input arguments, validating input arguments, and producing result types. The type inference process happens independent of a function body. The output of the type inference is used to search for a corresponding runtime implementation.
Instances of type inference can be created by using TypeInference.newBuilder()
.
See BuiltInFunctionDefinitions
for concrete usage examples.
getTypeInference
in interface FunctionDefinition
public Set<FunctionRequirement> getRequirements()
FunctionDefinition
getRequirements
in interface FunctionDefinition
public boolean isDeterministic()
FunctionDefinition
It returns true
if and only if a call to this function is guaranteed to
always return the same result given the same parameters. true
is assumed by
default. If the function is not pure functional like random(), date(), now(), ...
this method must return false
.
isDeterministic
in interface FunctionDefinition
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