Package 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

Modifier and Type	Field	Description
private CallImplementor	implementor

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

method, parameters

Constructor Summary

Constructors

Modifier	Constructor	Description
private	ScalarFunctionImpl(java.lang.reflect.Method method, CallImplementor implementor)	Private constructor.

Method Summary

Modifier and Type	Method	Description
static ScalarFunction	create(java.lang.Class<?> clazz, java.lang.String methodName)	Creates ScalarFunction from given class.
static ScalarFunction	create(java.lang.reflect.Method method)	Creates ScalarFunction from given method.
static com.google.common.collect.ImmutableMultimap<java.lang.String,ScalarFunction>	createAll(java.lang.Class<?> clazz)	Creates ScalarFunction for each method in a given class.
private static CallImplementor	createImplementor(java.lang.reflect.Method method)
CallImplementor	getImplementor()	Returns implementor that translates the function to linq4j expression.
private static NullPolicy	getNullPolicy(java.lang.reflect.Method m)
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, classHasPublicZeroArgsConstructor, findMethod, 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

Field Detail

implementor

private final CallImplementor implementor

Constructor Detail

ScalarFunctionImpl

private ScalarFunctionImpl(java.lang.reflect.Method method,
                           CallImplementor implementor)

Private constructor.

Method Detail

createAll

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

Creates ScalarFunction for each method in a given class.

create

public static ScalarFunction create(java.lang.Class<?> clazz,
                                    java.lang.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(java.lang.reflect.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

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.

createImplementor

private static CallImplementor createImplementor(java.lang.reflect.Method method)

getNullPolicy

private static NullPolicy getNullPolicy(java.lang.reflect.Method m)

getReturnType

public RelDataType getReturnType(RelDataTypeFactory typeFactory,
                                 SqlOperatorBinding opBinding)