org.apache.flink.table.planner.functions.inference

Class LookupCallContext

java.lang.Object

org.apache.flink.table.planner.functions.inference.AbstractSqlCallContext

org.apache.flink.table.planner.functions.inference.LookupCallContext

All Implemented Interfaces:

CallContext

@Internal
public class LookupCallContext
extends AbstractSqlCallContext

The CallContext of a LookupTableSource runtime function.

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.flink.table.planner.functions.inference.AbstractSqlCallContext

AbstractSqlCallContext.LiteralValueAccessor

Constructor Summary

Constructors

Constructor and Description
LookupCallContext(DataTypeFactory dataTypeFactory, UserDefinedFunction function, LogicalType inputType, Map<Integer,LookupJoinUtil.LookupKey> lookupKeys, int[] lookupKeyOrder, LogicalType lookupType)

Method Summary

Modifier and Type	Method and Description
List<DataType>	getArgumentDataTypes() Returns a resolved list of the call's argument types.
<T> Optional<T>	getArgumentValue(int pos, Class<T> clazz) Returns the literal value of the argument at the given position, given that the argument is a literal, is not null, and can be expressed as an instance of the provided class.
Optional<DataType>	getOutputDataType() Returns the inferred output data type of the function call.
boolean	isArgumentLiteral(int pos) Returns whether the argument at the given position is a value literal.
boolean	isArgumentNull(int pos) Returns true if the argument at the given position is a literal and null, false otherwise.

Methods inherited from class org.apache.flink.table.planner.functions.inference.AbstractSqlCallContext

getDataTypeFactory, getFunctionDefinition, getLiteralValueAs, getName, isGroupedAggregation

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.flink.table.types.inference.CallContext

fail, newValidationError

Constructor Detail

LookupCallContext

public LookupCallContext(DataTypeFactory dataTypeFactory,
                         UserDefinedFunction function,
                         LogicalType inputType,
                         Map<Integer,LookupJoinUtil.LookupKey> lookupKeys,
                         int[] lookupKeyOrder,
                         LogicalType lookupType)

Method Detail

isArgumentLiteral

public boolean isArgumentLiteral(int pos)

Description copied from interface: CallContext

Returns whether the argument at the given position is a value literal.

isArgumentNull

public boolean isArgumentNull(int pos)

Description copied from interface: CallContext

Returns true if the argument at the given position is a literal and null, false otherwise.

Use CallContext.isArgumentLiteral(int) before to check if the argument is actually a literal.

getArgumentValue

public <T> Optional<T> getArgumentValue(int pos,
                                        Class<T> clazz)

Description copied from interface: CallContext

Returns the literal value of the argument at the given position, given that the argument is a literal, is not null, and can be expressed as an instance of the provided class.

It supports conversions to default conversion classes of LogicalTypes. This method should not be called with other classes.

Use CallContext.isArgumentLiteral(int) before to check if the argument is actually a literal.

getArgumentDataTypes

public List<DataType> getArgumentDataTypes()

Description copied from interface: CallContext

Returns a resolved list of the call's argument types. It also includes a type for every argument in a vararg function call.

getOutputDataType

public Optional<DataType> getOutputDataType()

Description copied from interface: CallContext

Returns the inferred output data type of the function call.

It does this by inferring the input argument data type using ArgumentTypeStrategy.inferArgumentType(CallContext, int, boolean) of a wrapping call (if available) where this function call is an argument. For example, takes_string(this_function(NULL)) would lead to a DataTypes.STRING() because the wrapping call expects a string argument.