org.apache.calcite.schema.impl

Class ScalarFunctionImpl

java.lang.Object

org.apache.calcite.schema.impl.ReflectiveFunctionBase

org.apache.calcite.schema.impl.ScalarFunctionImpl

All Implemented Interfaces:

Function, ImplementableFunction, ScalarFunction

public class ScalarFunctionImpl
extends ReflectiveFunctionBase
implements ScalarFunction, ImplementableFunction

Implementation of ScalarFunction.

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.calcite.schema.impl.ReflectiveFunctionBase

ReflectiveFunctionBase.ParameterListBuilder

Field Summary

Fields inherited from class org.apache.calcite.schema.impl.ReflectiveFunctionBase

method, parameters

Method Summary

Modifier and Type	Method and Description
static @Nullable ScalarFunction	create(Class<?> clazz, String methodName) Creates ScalarFunction from given class.
static ScalarFunction	create(Method method) Creates ScalarFunction from given method.
static com.google.common.collect.ImmutableMultimap<String,ScalarFunction>	createAll(Class<?> clazz) Deprecated.
static ScalarFunction	createUnsafe(Method method) Creates unsafe version of ScalarFunction from any method.
static com.google.common.collect.ImmutableMultimap<String,Function>	functions(Class<?> clazz) Returns a map of all functions based on the methods in a given class.
CallImplementor	getImplementor() Returns implementor that translates the function to linq4j expression.
RelDataType	getReturnType(RelDataTypeFactory typeFactory) Returns the return type of this function, constructed using the given type factory.
RelDataType	getReturnType(RelDataTypeFactory typeFactory, SqlOperatorBinding opBinding)

Methods inherited from class org.apache.calcite.schema.impl.ReflectiveFunctionBase

builder, getParameters

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.calcite.schema.Function

getParameters

Method Detail

createAll

@Deprecated
public static com.google.common.collect.ImmutableMultimap<String,ScalarFunction> createAll(Class<?> clazz)

Deprecated.

Creates ScalarFunction for each method in a given class.

functions

public static com.google.common.collect.ImmutableMultimap<String,Function> functions(Class<?> clazz)

Returns a map of all functions based on the methods in a given class. It is keyed by method names and maps to both ScalarFunction and TableFunction.

create

public static @Nullable ScalarFunction create(Class<?> clazz,
                                              String methodName)

Creates ScalarFunction from given class.

If a method of the given name is not found or it does not suit, returns null.

Parameters:

clazz - class that is used to implement the function

methodName - Method name (typically "eval")

Returns:

created ScalarFunction or null

create

public static ScalarFunction create(Method method)

Creates ScalarFunction from given method. When eval method does not suit, null is returned.

Parameters:

method - method that is used to implement the function

Returns:

created ScalarFunction or null

createUnsafe

public static ScalarFunction createUnsafe(Method method)

Creates unsafe version of ScalarFunction from any method. The method does not need to be static or belong to a class with default constructor. It is the responsibility of the underlying engine to initialize the UDF object that contain the method.

Parameters:

method - method that is used to implement the function

getReturnType

public RelDataType getReturnType(RelDataTypeFactory typeFactory)

Description copied from interface: ScalarFunction

Returns the return type of this function, constructed using the given type factory.

Specified by:

getReturnType in interface ScalarFunction

Parameters:

typeFactory - Type factory

getImplementor

public CallImplementor getImplementor()

Description copied from interface: ImplementableFunction

Returns implementor that translates the function to linq4j expression.

Specified by:

getImplementor in interface ImplementableFunction

Returns:

implementor that translates the function to linq4j expression.

getReturnType

public RelDataType getReturnType(RelDataTypeFactory typeFactory,
                                 SqlOperatorBinding opBinding)