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ReduceTaskTKey, TValue, TOutput Class

Abstract base class for reduce tasks.
Inheritance Hierarchy
SystemObject
  Ookii.Jumbo.JetConfigurable
    Ookii.Jumbo.Jet.TasksReduceTaskTKey, TValue, TOutput

Namespace:  Ookii.Jumbo.Jet.Tasks
Assembly:  Ookii.Jumbo.Jet (in Ookii.Jumbo.Jet.dll) Version: 2.0.0
Syntax
public abstract class ReduceTask<TKey, TValue, TOutput> : Configurable, 
	ITask<Pair<TKey, TValue>, TOutput>
where TKey : Object, IComparable<TKey>

Type Parameters

TKey
The type of the key of the input records.
TValue
The type of the value of the input records.
TOutput
The type of the output records.

The ReduceTaskTKey, TValue, TOutput type exposes the following members.

Constructors
  NameDescription
Protected methodReduceTaskTKey, TValue, TOutput
Initializes a new instance of the ReduceTaskTKey, TValue, TOutput class.
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Properties
  NameDescription
Public propertyDfsConfiguration
Gets or sets the configuration used to access the Distributed File System.
(Inherited from Configurable.)
Public propertyJetConfiguration
Gets or sets the configuration used to access the Jet servers.
(Inherited from Configurable.)
Public propertyTaskContext
Gets or sets the configuration for the task attempt.
(Inherited from Configurable.)
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Methods
  NameDescription
Public methodEquals
Determines whether the specified object is equal to the current object.
(Inherited from Object.)
Protected methodFinalize
Allows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection.
(Inherited from Object.)
Public methodGetHashCode
Serves as the default hash function.
(Inherited from Object.)
Public methodGetType
Gets the Type of the current instance.
(Inherited from Object.)
Protected methodMemberwiseClone
Creates a shallow copy of the current Object.
(Inherited from Object.)
Public methodNotifyConfigurationChanged
Indicates the configuration has been changed. ApplyConfiguration(Object, DfsConfiguration, JetConfiguration, TaskContext) calls this method after setting the configuration.
(Overrides ConfigurableNotifyConfigurationChanged.)
Protected methodReduce
Reduces the values for the specified key.
Public methodRun
Runs the task.
Public methodToString
Returns a string that represents the current object.
(Inherited from Object.)
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Remarks
Note Note
This task requires that the input is sorted by key.

Because the ReduceTaskTKey, TValue, TOutput class is a pull task, it is not recommended to use it as the receiving stage of an in-process channel.

If the reduce function could be calculated incrementally, AccumulatorTaskTKey, TValue often offers much better performance than sorting and using a reduce task.

You may specify the AllowRecordReuseAttribute attribute on classes deriving from this type only if TKey is a value type or implements ICloneable.

See Also