TaskContext (Spark 3.4.0 JavaDoc)

Object
- org.apache.spark.TaskContext

All Implemented Interfaces:

java.io.Serializable

Direct Known Subclasses:

BarrierTaskContext
```
public abstract class TaskContext
extends Object
implements java.io.Serializable
```
Contextual information about a task which can be read or mutated during execution. To access the TaskContext for a running task, use:
```
   org.apache.spark.TaskContext.get()
 
```
See Also:

Serialized Form

Constructor Summary

Constructors
Constructor and Description

TaskContext()

Constructors
Constructor and Description
`TaskContext()`

Method Summary

All Methods Static Methods Instance Methods Abstract Methods Concrete Methods
Modifier and Type	Method and Description
`<U> TaskContext`	`addTaskCompletionListener(scala.Function1<TaskContext,U> f)` Adds a listener in the form of a Scala closure to be executed on task completion.
`abstract TaskContext`	`addTaskCompletionListener(TaskCompletionListener listener)` Adds a (Java friendly) listener to be executed on task completion.
`TaskContext`	`addTaskFailureListener(scala.Function2<TaskContext,Throwable,scala.runtime.BoxedUnit> f)` Adds a listener to be executed on task failure (which includes completion listener failure, if the task body did not already fail).
`abstract TaskContext`	`addTaskFailureListener(TaskFailureListener listener)` Adds a listener to be executed on task failure (which includes completion listener failure, if the task body did not already fail).
`abstract int`	`attemptNumber()` How many times this task has been attempted.
`abstract int`	`cpus()` CPUs allocated to the task.
`static TaskContext`	`get()` Return the currently active TaskContext.
`abstract String`	`getLocalProperty(String key)` Get a local property set upstream in the driver, or null if it is missing.
`abstract scala.collection.Seq<Source>`	`getMetricsSources(String sourceName)` ::DeveloperApi:: Returns all metrics sources with the given name which are associated with the instance which runs the task.
`static int`	`getPartitionId()` Returns the partition id of currently active TaskContext.
`abstract boolean`	`isCompleted()` Returns true if the task has completed.
`abstract boolean`	`isInterrupted()` Returns true if the task has been killed.
`abstract int`	`numPartitions()` Total number of partitions in the stage that this task belongs to.
`abstract int`	`partitionId()` The ID of the RDD partition that is computed by this task.
`abstract scala.collection.immutable.Map<String,ResourceInformation>`	`resources()` Resources allocated to the task.
`abstract java.util.Map<String,ResourceInformation>`	`resourcesJMap()` (java-specific) Resources allocated to the task.
`abstract int`	`stageAttemptNumber()` How many times the stage that this task belongs to has been attempted.
`abstract int`	`stageId()` The ID of the stage that this task belong to.
`abstract long`	`taskAttemptId()` An ID that is unique to this task attempt (within the same SparkContext, no two task attempts will share the same attempt ID).
`abstract org.apache.spark.executor.TaskMetrics`	`taskMetrics()`

Methods inherited from class Object
equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Constructor Detail
  - TaskContext
```
public TaskContext()
```
- Method Detail
  - get
```
public static TaskContext get()
```
    Return the currently active TaskContext. This can be called inside of user functions to access contextual information about running tasks.
    
    Returns:
    
    (undocumented)
  - getPartitionId
```
public static int getPartitionId()
```
    Returns the partition id of currently active TaskContext. It will return 0 if there is no active TaskContext for cases like local execution.
    
    Returns:
    
    (undocumented)
  - isCompleted
```
public abstract boolean isCompleted()
```
    Returns true if the task has completed.
    
    Returns:
    
    (undocumented)
  - isInterrupted
```
public abstract boolean isInterrupted()
```
    Returns true if the task has been killed.
    
    Returns:
    
    (undocumented)
  - addTaskCompletionListener
```
public abstract TaskContext addTaskCompletionListener(TaskCompletionListener listener)
```
    Adds a (Java friendly) listener to be executed on task completion. This will be called in all situations - success, failure, or cancellation. Adding a listener to an already completed task will result in that listener being called immediately.
    Two listeners registered in the same thread will be invoked in reverse order of registration if the task completes after both are registered. There are no ordering guarantees for listeners registered in different threads, or for listeners registered after the task completes. Listeners are guaranteed to execute sequentially.
    An example use is for HadoopRDD to register a callback to close the input stream.
    Exceptions thrown by the listener will result in failure of the task.
    
    Parameters:
    
    listener - (undocumented)
    
    Returns:
    
    (undocumented)
  - addTaskCompletionListener
```
public <U> TaskContext addTaskCompletionListener(scala.Function1<TaskContext,U> f)
```
    Adds a listener in the form of a Scala closure to be executed on task completion. This will be called in all situations - success, failure, or cancellation. Adding a listener to an already completed task will result in that listener being called immediately.
    An example use is for HadoopRDD to register a callback to close the input stream.
    Exceptions thrown by the listener will result in failure of the task.
    
    Parameters:
    
    f - (undocumented)
    
    Returns:
    
    (undocumented)
  - addTaskFailureListener
```
public abstract TaskContext addTaskFailureListener(TaskFailureListener listener)
```
    Adds a listener to be executed on task failure (which includes completion listener failure, if the task body did not already fail). Adding a listener to an already failed task will result in that listener being called immediately.
    Note: Prior to Spark 3.4.0, failure listeners were only invoked if the main task body failed.
    
    Parameters:
    
    listener - (undocumented)
    
    Returns:
    
    (undocumented)
  - addTaskFailureListener
```
public TaskContext addTaskFailureListener(scala.Function2<TaskContext,Throwable,scala.runtime.BoxedUnit> f)
```
    Adds a listener to be executed on task failure (which includes completion listener failure, if the task body did not already fail). Adding a listener to an already failed task will result in that listener being called immediately.
    Note: Prior to Spark 3.4.0, failure listeners were only invoked if the main task body failed.
    
    Parameters:
    
    f - (undocumented)
    
    Returns:
    
    (undocumented)
  - stageId
```
public abstract int stageId()
```
    The ID of the stage that this task belong to.
    
    Returns:
    
    (undocumented)
  - stageAttemptNumber
```
public abstract int stageAttemptNumber()
```
    How many times the stage that this task belongs to has been attempted. The first stage attempt will be assigned stageAttemptNumber = 0, and subsequent attempts will have increasing attempt numbers.
    
    Returns:
    
    (undocumented)
  - partitionId
```
public abstract int partitionId()
```
    The ID of the RDD partition that is computed by this task.
    
    Returns:
    
    (undocumented)
  - numPartitions
```
public abstract int numPartitions()
```
    Total number of partitions in the stage that this task belongs to.
    
    Returns:
    
    (undocumented)
  - attemptNumber
```
public abstract int attemptNumber()
```
    How many times this task has been attempted. The first task attempt will be assigned attemptNumber = 0, and subsequent attempts will have increasing attempt numbers.
    
    Returns:
    
    (undocumented)
  - taskAttemptId
```
public abstract long taskAttemptId()
```
    An ID that is unique to this task attempt (within the same SparkContext, no two task attempts will share the same attempt ID). This is roughly equivalent to Hadoop's TaskAttemptID.
    
    Returns:
    
    (undocumented)
  - getLocalProperty
```
public abstract String getLocalProperty(String key)
```
    Get a local property set upstream in the driver, or null if it is missing. See also org.apache.spark.SparkContext.setLocalProperty.
    
    Parameters:
    
    key - (undocumented)
    
    Returns:
    
    (undocumented)
  - cpus
```
public abstract int cpus()
```
    CPUs allocated to the task.
    
    Returns:
    
    (undocumented)
  - resources
```
public abstract scala.collection.immutable.Map<String,ResourceInformation> resources()
```
    Resources allocated to the task. The key is the resource name and the value is information about the resource. Please refer to ResourceInformation for specifics.
    
    Returns:
    
    (undocumented)
  - resourcesJMap
```
public abstract java.util.Map<String,ResourceInformation> resourcesJMap()
```
    (java-specific) Resources allocated to the task. The key is the resource name and the value is information about the resource. Please refer to ResourceInformation for specifics.
    
    Returns:
    
    (undocumented)
  - taskMetrics
```
public abstract org.apache.spark.executor.TaskMetrics taskMetrics()
```
  - getMetricsSources
```
public abstract scala.collection.Seq<Source> getMetricsSources(String sourceName)
```
    ::DeveloperApi:: Returns all metrics sources with the given name which are associated with the instance which runs the task. For more information see org.apache.spark.metrics.MetricsSystem.
    
    Parameters:
    
    sourceName - (undocumented)
    
    Returns:
    
    (undocumented)

Class TaskContext

Constructor Summary

Method Summary

Methods inherited from class Object

Constructor Detail

TaskContext

Method Detail

get

getPartitionId

isCompleted

isInterrupted

addTaskCompletionListener

addTaskCompletionListener

addTaskFailureListener

addTaskFailureListener

stageId

stageAttemptNumber

partitionId

numPartitions

attemptNumber

taskAttemptId

getLocalProperty

cpus

resources

resourcesJMap

taskMetrics

getMetricsSources