cascading.operation.aggregator
Class First
java.lang.Object
cascading.operation.BaseOperation<Tuple[]>
cascading.operation.aggregator.ExtentBase
cascading.operation.aggregator.First
- All Implemented Interfaces:
- Aggregator<Tuple[]>, Operation<Tuple[]>, Serializable
public class First
- extends ExtentBase
Class First is an Aggregator
that returns the first Tuple
encountered.
By default, it returns the first Tuple of Fields.ARGS
found.
- See Also:
- Serialized Form
Fields inherited from interface cascading.operation.Operation |
ANY |
Constructor Summary |
First()
Selects and returns the first argument Tuple encountered. |
First(Fields fieldDeclaration)
Selects and returns the first argument Tuple encountered. |
First(Fields fieldDeclaration,
Tuple... ignoreTuples)
Selects and returns the first argument Tuple encountered, unless the Tuple
is a member of the set ignoreTuples. |
First
public First()
- Selects and returns the first argument Tuple encountered.
First
@ConstructorProperties(value="fieldDeclaration")
public First(Fields fieldDeclaration)
- Selects and returns the first argument Tuple encountered.
- Parameters:
fieldDeclaration
- of type Fields
First
@ConstructorProperties(value={"fieldDeclaration","ignoreTuples"})
public First(Fields fieldDeclaration,
Tuple... ignoreTuples)
- Selects and returns the first argument Tuple encountered, unless the Tuple
is a member of the set ignoreTuples.
- Parameters:
fieldDeclaration
- of type FieldsignoreTuples
- of type Tuple...
performOperation
protected void performOperation(Tuple[] context,
TupleEntry entry)
- Specified by:
performOperation
in class ExtentBase
Copyright © 2007-2012 Concurrent, Inc. All Rights Reserved.