org.apache.flink.table.functions.hive

Class HiveSimpleUDF

java.lang.Object

org.apache.flink.table.functions.UserDefinedFunction

org.apache.flink.table.functions.ScalarFunction

org.apache.flink.table.functions.hive.HiveScalarFunction<org.apache.hadoop.hive.ql.exec.UDF>

org.apache.flink.table.functions.hive.HiveSimpleUDF

All Implemented Interfaces:

Serializable, FunctionDefinition, HiveFunction

@Internal
public class HiveSimpleUDF
extends HiveScalarFunction<org.apache.hadoop.hive.ql.exec.UDF>

A ScalarFunction implementation that calls Hive's UDF.

See Also:

Serialized Form

Field Summary

Fields inherited from class org.apache.flink.table.functions.hive.HiveScalarFunction

argTypes, constantArguments, function, hiveFunctionWrapper, returnInspector

Constructor Summary

Constructors

Constructor and Description
HiveSimpleUDF(HiveFunctionWrapper<org.apache.hadoop.hive.ql.exec.UDF> hiveFunctionWrapper)

Method Summary

Modifier and Type	Method and Description
Object	evalInternal(Object[] args) Evaluation logical, args will be wrapped when is a single array.
DataType	getHiveResultType(Object[] constantArguments, DataType[] argTypes) Get result type by arguments and argTypes.
void	openInternal() See UserDefinedFunction.open(FunctionContext).

Methods inherited from class org.apache.flink.table.functions.hive.HiveScalarFunction

eval, getResultType, isDeterministic, open, setArgumentTypesAndConstants

Methods inherited from class org.apache.flink.table.functions.ScalarFunction

getKind, getParameterTypes

Methods inherited from class org.apache.flink.table.functions.UserDefinedFunction

close, functionIdentifier, toString

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.flink.table.functions.FunctionDefinition

getRequirements

Constructor Detail

HiveSimpleUDF

public HiveSimpleUDF(HiveFunctionWrapper<org.apache.hadoop.hive.ql.exec.UDF> hiveFunctionWrapper)

Method Detail

openInternal

public void openInternal()

Description copied from class: HiveScalarFunction

See UserDefinedFunction.open(FunctionContext).

Specified by:

openInternal in class HiveScalarFunction<org.apache.hadoop.hive.ql.exec.UDF>

evalInternal

public Object evalInternal(Object[] args)

Description copied from class: HiveScalarFunction

Evaluation logical, args will be wrapped when is a single array.

Specified by:

evalInternal in class HiveScalarFunction<org.apache.hadoop.hive.ql.exec.UDF>

getHiveResultType

public DataType getHiveResultType(Object[] constantArguments,
                                  DataType[] argTypes)

Description copied from interface: HiveFunction

Get result type by arguments and argTypes.

We can't use getResultType(Object[], Class[]). The Class[] is the classes of what is defined in eval(), for example, if eval() is "public Integer eval(Double)", the argTypes would be Class[Double]. However, in our wrapper, the signature of eval() is "public Object eval(Object... args)", which means we cannot get any info from the interface.

Parameters:

constantArguments - arguments of a function call (only literal arguments are passed, nulls for non-literal ones)

argTypes - types of arguments

Returns:

result type.