ValueMapper (Storm 2.7.1 API)

java.lang.Object
- org.apache.storm.streams.operations.mappers.ValueMapper<T>

Type Parameters:

T - the value type

All Implemented Interfaces:

Serializable, Function<Tuple,T>, TupleValueMapper<T>, Operation
```
public class ValueMapper<T>
extends Object
implements TupleValueMapper<T>
```
Extracts a single typed value from a tuple.

See Also:

Serialized Form

- Constructor Summary
  
  Constructors
  Constructor Description
  
  ValueMapper(int index)
  Constructs a new ValueMapper that extracts the value at index 'i' from a tuple.
- Method Summary
  
  All Methods Instance Methods Concrete Methods
  Modifier and Type Method Description
  
  T apply(Tuple input)
  Applies this function to the given argument.
  - Methods inherited from class java.lang.Object
    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Constructor Detail
  - ValueMapper
```
public ValueMapper(int index)
```
    Constructs a new ValueMapper that extracts the value at index 'i' from a tuple.
    
    Parameters:
    
    index - the index
- Method Detail
  - apply
```
public T apply(Tuple input)
```
    Description copied from interface: Function
    
    Applies this function to the given argument.
    
    Specified by:
    
    apply in interface Function<Tuple,T>
    
    Parameters:
    
    input - the input to the function
    
    Returns:
    
    the function result