Task (OpenDJ Public API Javadoc 6.5.6 Documentation)

java.lang.Object
- org.opends.server.backends.task.Task

All Implemented Interfaces:

Comparable<Task>

Direct Known Subclasses:

AddSchemaFileTask, BackupTask, DisconnectClientTask, EnterLockdownModeTask, ExportTask, ImportTask, InitializeTargetTask, InitializeTask, LeaveLockdownModeTask, PurgeConflictsHistoricalTask, RebuildTask, ResetChangeNumberTask, RestoreTask, SetGenerationIdTask, ShutdownTask
```
public abstract class Task
extends Object
implements Comparable<Task>
```
This class defines a task that may be executed by the task backend within the Directory Server.

Constructor Summary

Constructors
Constructor and Description

Task()

Constructors
Constructor and Description
`Task()`

Method Summary

All Methods Instance Methods Abstract Methods Concrete Methods
Modifier and Type	Method and Description
`void`	`addLogMessage(Severity severity, LocalizableMessage message)` Adds a log message to the set of messages logged by this task.
`void`	`addLogMessage(Severity severity, LocalizableMessage message, Throwable exception)` Adds a log message to the set of messages logged by this task.
`int`	`compareTo(Task task)` Compares this task with the provided task for the purposes of ordering in a sorted list.
`TaskState`	`execute()` Begins execution for this task.
`long`	`getActualStartTime()` Retrieves the time that this task actually started running, if it has started.
`LocalizableMessage`	`getAttributeDisplayName(String name)` Given an attribute type name returns and locale sensitive representation.
`long`	`getCompletionTime()` Retrieves the time that this task completed all of its associated processing (regardless of whether it was successful), if it has completed.
`LinkedList<String>`	`getDependencyIDs()` Retrieves the set of task IDs for any tasks on which this task is dependent.
`LocalizableMessage`	`getDisplayName()` Gets a message that identifies this type of task suitable for presentation to humans in monitoring tools.
`FailedDependencyAction`	`getFailedDependencyAction()` Retrieves the action that should be taken if any of the dependencies for this task do not complete successfully.
`protected TaskState`	`getFinalTaskState()` Returns a state for this task after processing has completed.
`List<LocalizableMessage>`	`getLogMessages()` Retrieves the set of messages that were logged by this task.
`LinkedList<String>`	`getNotifyOnCompletionAddresses()` Retrieves the set of e-mail addresses for the users that should receive a notification message when processing for this task has completed.
`LinkedList<String>`	`getNotifyOnErrorAddresses()` Retrieves the set of e-mail addresses for the users that should receive a notification message if processing for this task does not complete successfully.
`Operation`	`getOperation()` Retrieves the operation used to create this task in the server.
`String`	`getRecurringTaskID()` Retrieves the unique identifier assigned to the recurring task that is associated with this task, if there is one.
`long`	`getScheduledStartTime()` Retrieves the scheduled start time for this task, if there is one.
`protected ServerContext`	`getServerContext()` Returns the server context.
`Entry`	`getTaskEntry()` Retrieves the entry containing the definition for this task.
`Dn`	`getTaskEntryDN()` Retrieves the DN of the entry containing the definition for this task.
`String`	`getTaskID()` Retrieves the unique identifier assigned to this task.
`protected TaskState`	`getTaskInterruptState()` Gets the interrupt state for this task that was set as a result of a call to `interruptTask(TaskState, LocalizableMessage)`.
`TaskState`	`getTaskState()` Retrieves the current state for this task.
`void`	`initializeTask()` Performs any task-specific initialization that may be required before processing can start.
`void`	`initializeTaskInternal(ServerContext serverContext, TaskScheduler taskScheduler, Entry taskEntry)` Performs generic initialization for this task based on the information in the provided task entry.
`void`	`interruptTask(TaskState interruptState, LocalizableMessage interruptReason)` Performs any necessary processing to prematurely interrupt the execution of this task.
`boolean`	`isCancelled()` Indicates whether this task has been cancelled.
`boolean`	`isInterruptable()` Indicates whether this task is interruptible or not.
`boolean`	`isRecurring()` Indicates whether this task is an iteration of some recurring task.
`protected void`	`replaceAttributeValue(String name, Object value)` Replaces an attribute values of the task entry.
`protected abstract TaskState`	`runTask()` Performs the actual core processing for this task.
`protected void`	`sendNotificationEMailMessage()` If appropriate, send an e-mail message with information about the completed task.
`protected void`	`setCompletionTime(long completionTime)` Sets the completion time for this task and updates the associated task entry as necessary.
`void`	`setOperation(Operation operation)` Specifies the operation used to create this task in the server.
`protected void`	`setTaskInterruptState(TaskState state)` Sets a state for this task that is the result of a call to `interruptTask(TaskState, LocalizableMessage)`.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Constructor Detail
  - Task
```
public Task()
```
- Method Detail
  - getServerContext
```
protected ServerContext getServerContext()
```
    Returns the server context.
    
    Returns:
    
    the server context.
  - getDisplayName
```
public LocalizableMessage getDisplayName()
```
    Gets a message that identifies this type of task suitable for presentation to humans in monitoring tools.
    
    Returns:
    
    name of task
  - getAttributeDisplayName
```
public LocalizableMessage getAttributeDisplayName(String name)
```
    Given an attribute type name returns and locale sensitive representation.
    
    Parameters:
    
    name - of an attribute type associated with the object class that represents this entry in the directory
    
    Returns:
    
    LocalizableMessage display name
  - initializeTaskInternal
```
public final void initializeTaskInternal(ServerContext serverContext,
                                         TaskScheduler taskScheduler,
                                         Entry taskEntry)
                                  throws InitializationException
```
    Performs generic initialization for this task based on the information in the provided task entry.
    
    Parameters:
    
    serverContext - The server context.
    
    taskScheduler - The scheduler with which this task is associated.
    
    taskEntry - The entry containing the task configuration.
    
    Throws:
    
    InitializationException - If a problem occurs while performing the initialization.
  - getTaskEntryDN
```
public final Dn getTaskEntryDN()
```
    Retrieves the DN of the entry containing the definition for this task.
    
    Returns:
    
    The DN of the entry containing the definition for this task.
  - getTaskEntry
```
public final Entry getTaskEntry()
```
    Retrieves the entry containing the definition for this task.
    
    Returns:
    
    The entry containing the definition for this task.
  - getOperation
```
public final Operation getOperation()
```
    Retrieves the operation used to create this task in the server. Note that this will only be available when the task is first added to the scheduler, and it should only be accessed from within the initializeTask method (and even that method should not depend on it always being available, since it will not be available if the server is restarted and the task needs to be reinitialized).
    
    Returns:
    
    The operation used to create this task in the server, or null if it is not available.
  - setOperation
```
public final void setOperation(Operation operation)
```
    Specifies the operation used to create this task in the server.
    
    Parameters:
    
    operation - The operation used to create this task in the server.
  - getTaskID
```
public final String getTaskID()
```
    Retrieves the unique identifier assigned to this task.
    
    Returns:
    
    The unique identifier assigned to this task.
  - getRecurringTaskID
```
public final String getRecurringTaskID()
```
    Retrieves the unique identifier assigned to the recurring task that is associated with this task, if there is one.
    
    Returns:
    
    The unique identifier assigned to the recurring task that is associated with this task, or null if it is not associated with any recurring task.
  - getTaskState
```
public final TaskState getTaskState()
```
    Retrieves the current state for this task.
    
    Returns:
    
    The current state for this task.
  - isRecurring
```
public boolean isRecurring()
```
    Indicates whether this task is an iteration of some recurring task.
    
    Returns:
    
    boolean where true indicates that this task is recurring, false otherwise.
  - isCancelled
```
public boolean isCancelled()
```
    Indicates whether this task has been cancelled.
    
    Returns:
    
    boolean where true indicates that this task was cancelled either before or during execution
  - setTaskInterruptState
```
protected void setTaskInterruptState(TaskState state)
```
    Sets a state for this task that is the result of a call to interruptTask(TaskState, LocalizableMessage). It may take this task some time to actually cancel to that actual state may differ until quiescence.
    
    Parameters:
    
    state - for this task once it has canceled whatever it is doing
  - getTaskInterruptState
```
protected TaskState getTaskInterruptState()
```
    Gets the interrupt state for this task that was set as a result of a call to interruptTask(TaskState, LocalizableMessage).
    
    Returns:
    
    interrupt state for this task
  - getFinalTaskState
```
protected TaskState getFinalTaskState()
```
    Returns a state for this task after processing has completed. If the task was interrupted with a call to interruptTask(TaskState, LocalizableMessage) then that method's interruptState is returned here. Otherwise this method returns TaskState.COMPLETED_SUCCESSFULLY. It is assumed that if there were errors during task processing that task state will have been derived in some other way.
    
    Returns:
    
    state for this task after processing has completed
  - replaceAttributeValue
```
protected void replaceAttributeValue(String name,
                                     Object value)
```
    Replaces an attribute values of the task entry.
    
    Parameters:
    
    name - The name of the attribute that must be replaced.
    
    value - The value that must replace the previous values of the attribute.
  - getScheduledStartTime
```
public final long getScheduledStartTime()
```
    Retrieves the scheduled start time for this task, if there is one. The value returned will be in the same format as the return value for System.currentTimeMillis(). Any value representing a time in the past, or any negative value, should be taken to mean that the task should be considered eligible for immediate execution.
    
    Returns:
    
    The scheduled start time for this task.
  - getActualStartTime
```
public final long getActualStartTime()
```
    Retrieves the time that this task actually started running, if it has started. The value returned will be in the same format as the return value for System.currentTimeMillis().
    
    Returns:
    
    The time that this task actually started running, or -1 if it has not yet been started.
  - getCompletionTime
```
public final long getCompletionTime()
```
    Retrieves the time that this task completed all of its associated processing (regardless of whether it was successful), if it has completed. The value returned will be in the same format as the return value for System.currentTimeMillis().
    
    Returns:
    
    The time that this task actually completed running, or -1 if it has not yet completed.
  - setCompletionTime
```
protected void setCompletionTime(long completionTime)
```
    Sets the completion time for this task and updates the associated task entry as necessary. It does not automatically persist the updated task information to disk.
    
    Parameters:
    
    completionTime - The completion time to use for this task.
  - getDependencyIDs
```
public final LinkedList<String> getDependencyIDs()
```
    Retrieves the set of task IDs for any tasks on which this task is dependent. This list must not be directly modified by the caller.
    
    Returns:
    
    The set of task IDs for any tasks on which this task is dependent.
  - getFailedDependencyAction
```
public final FailedDependencyAction getFailedDependencyAction()
```
    Retrieves the action that should be taken if any of the dependencies for this task do not complete successfully.
    
    Returns:
    
    The action that should be taken if any of the dependencies for this task do not complete successfully.
  - getNotifyOnCompletionAddresses
```
public final LinkedList<String> getNotifyOnCompletionAddresses()
```
    Retrieves the set of e-mail addresses for the users that should receive a notification message when processing for this task has completed. This notification will be sent to these users regardless of whether the task completed successfully. This list must not be directly modified by the caller.
    
    Returns:
    
    The set of e-mail addresses for the users that should receive a notification message when processing for this task has completed.
  - getNotifyOnErrorAddresses
```
public final LinkedList<String> getNotifyOnErrorAddresses()
```
    Retrieves the set of e-mail addresses for the users that should receive a notification message if processing for this task does not complete successfully. This list must not be directly modified by the caller.
    
    Returns:
    
    The set of e-mail addresses for the users that should receive a notification message if processing for this task does not complete successfully.
  - getLogMessages
```
public final List<LocalizableMessage> getLogMessages()
```
    Retrieves the set of messages that were logged by this task. This list must not be directly modified by the caller.
    
    Returns:
    
    The set of messages that were logged by this task.
  - addLogMessage
```
public void addLogMessage(Severity severity,
                          LocalizableMessage message)
```
    Adds a log message to the set of messages logged by this task. This method should not be called directly by tasks, but rather will be called indirectly through the ErrorLog.logError methods. It does not automatically persist the updated task information to disk.
    
    Parameters:
    
    severity - the severity of message.
    
    message - the log message.
  - addLogMessage
```
public void addLogMessage(Severity severity,
                          LocalizableMessage message,
                          Throwable exception)
```
    Adds a log message to the set of messages logged by this task. This method should not be called directly by tasks, but rather will be called indirectly through the ErrorLog.logError methods. It does not automatically persist the updated task information to disk.
    
    Parameters:
    
    severity - the severity of message.
    
    message - the log message.
    
    exception - the exception to log. May be null.
  - compareTo
```
public final int compareTo(Task task)
```
    Compares this task with the provided task for the purposes of ordering in a sorted list. Any completed task will always be ordered before an uncompleted task. If both tasks are completed, then they will be ordered by completion time. If both tasks are uncompleted, then a running task will always be ordered before one that has not started. If both are running, then they will be ordered by actual start time. If neither have started, then they will be ordered by scheduled start time. If all else fails, they will be ordered lexicographically by task ID.
    
    Specified by:
    
    compareTo in interface Comparable<Task>
    
    Parameters:
    
    task - The task to compare with this task.
    
    Returns:
    
    A negative value if the provided task should come before this task, a positive value if the provided task should come after this task, or zero if there is no difference with regard to their order.
  - execute
```
public final TaskState execute()
```
    Begins execution for this task. This is a wrapper around the runTask method that performs the appropriate set-up and tear-down. It should only be invoked by a task thread.
    
    Returns:
    
    The final state to use for the task.
  - sendNotificationEMailMessage
```
protected void sendNotificationEMailMessage()
                                     throws javax.mail.MessagingException
```
    If appropriate, send an e-mail message with information about the completed task.
    
    Throws:
    
    javax.mail.MessagingException - If a problem occurs while attempting to send the message.
  - initializeTask
```
public void initializeTask()
                    throws LdapException
```
    Performs any task-specific initialization that may be required before processing can start. This default implementation does not do anything, but subclasses may override it as necessary. This method will be called at the time the task is scheduled, and therefore any failure in this method will be returned to the client.
    
    Throws:
    
    LdapException - If a problem occurs during initialization that should be returned to the client.
  - runTask
```
protected abstract TaskState runTask()
```
    Performs the actual core processing for this task. This method should not return until all processing associated with this task has completed.
    
    Returns:
    
    The final state to use for the task.
  - interruptTask
```
public void interruptTask(TaskState interruptState,
                          LocalizableMessage interruptReason)
```
    Performs any necessary processing to prematurely interrupt the execution of this task. By default no action is performed, but if it is feasible to gracefully interrupt a task, then subclasses should override this method to do so. Implementations of this method are expected to call setTaskInterruptState(TaskState) if the interruption is accepted by this task.
    
    Parameters:
    
    interruptState - The state to use for the task if it is successfully interrupted.
    
    interruptReason - A human-readable explanation for the cancellation.
  - isInterruptable
```
public boolean isInterruptable()
```
    Indicates whether this task is interruptible or not.
    
    Returns:
    
    boolean where true indicates that this task can be interrupted.

Class Task

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

Task

Method Detail

getServerContext

getDisplayName

getAttributeDisplayName

initializeTaskInternal

getTaskEntryDN

getTaskEntry

getOperation

setOperation

getTaskID

getRecurringTaskID

getTaskState

isRecurring

isCancelled

setTaskInterruptState

getTaskInterruptState

getFinalTaskState

replaceAttributeValue

getScheduledStartTime

getActualStartTime

getCompletionTime

setCompletionTime

getDependencyIDs

getFailedDependencyAction

getNotifyOnCompletionAddresses

getNotifyOnErrorAddresses

getLogMessages

addLogMessage

addLogMessage

compareTo

execute

sendNotificationEMailMessage

initializeTask

runTask

interruptTask

isInterruptable