MapKeysFunction (Flink : 2.0-SNAPSHOT API)

java.lang.Object
- org.apache.flink.table.functions.UserDefinedFunction
- - org.apache.flink.table.functions.ScalarFunction
  - - org.apache.flink.table.runtime.functions.scalar.BuiltInScalarFunction
    - - org.apache.flink.table.runtime.functions.scalar.MapKeysFunction

All Implemented Interfaces:

Serializable, FunctionDefinition
```
@Internal
public class MapKeysFunction
extends BuiltInScalarFunction
```
Implementation of BuiltInFunctionDefinitions.MAP_KEYS.

See Also:

Serialized Form

- Constructor Summary
  
  Constructors
  Constructor Description
  
  MapKeysFunction(SpecializedFunction.SpecializedContext context)
- Method Summary
  
  All Methods Instance Methods Concrete Methods
  Modifier and Type Method Description
  
  ArrayData eval(MapData input)
  - Methods inherited from class org.apache.flink.table.runtime.functions.scalar.BuiltInScalarFunction
    getArgumentDataTypes, getOutputDataType, getRequirements, getTypeInference, isDeterministic
  - Methods inherited from class org.apache.flink.table.functions.ScalarFunction
    getKind, getParameterTypes, getResultType
  - Methods inherited from class org.apache.flink.table.functions.UserDefinedFunction
    close, functionIdentifier, open, 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
    supportsConstantFolding

Constructor Detail

MapKeysFunction

public MapKeysFunction(SpecializedFunction.SpecializedContext context)

Method Detail

eval

@Nullable
public ArrayData eval(@Nullable
                      MapData input)