Task (Apache Brooklyn)

All Superinterfaces:

java.util.concurrent.Future<T>, com.google.common.util.concurrent.ListenableFuture<T>, TaskAdaptable<T>

All Known Subinterfaces:

TaskInternal<T>

All Known Implementing Classes:

BasicTask, CompoundTask, DynamicSequentialTask, ForwardingTask, ParallelTask, ScheduledTask, SequentialTask
```
public interface Task<T>
extends com.google.common.util.concurrent.ListenableFuture<T>, TaskAdaptable<T>
```
Represents a unit of work for execution. When used with an ExecutionManager or ExecutionContext it will record submission time, execution start time, end time, and any result. A task can be submitted to the ExecutionManager or ExecutionContext, in which case it will be returned, or it may be created by submission of a Runnable or Callable and thereafter it can be treated just like a Future.

Method Summary

Methods
Modifier and Type	Method and Description
`void`	`blockUntilEnded()` Causes calling thread to block until the task is ended.
`boolean`	`blockUntilEnded(Duration timeout)` As `blockUntilEnded()`, but returning after the given timeout; true if the task has ended and false otherwise
`void`	`blockUntilStarted()` Causes calling thread to block until the task is started.
`boolean`	`cancel(boolean mayInterruptIfRunning)` As `Future.cancel(boolean)`.
`T`	`get(Duration duration)` As `Future.get(long, java.util.concurrent.TimeUnit)`
`java.lang.String`	`getDescription()`
`java.lang.String`	`getDisplayName()`
`long`	`getEndTimeUtc()` if `Future.isDone()` (for any reason) returns the time when the task ended; guaranteed to be >= `getStartTimeUtc()` > 0 if ended, or -1 otherwise
`java.lang.String`	`getId()`
`long`	`getStartTimeUtc()` if `isBegun()` returns the time when the task was starts; guaranteed to be >= `getSubmitTimeUtc()` > 0 if started, or -1 otherwise
`java.lang.String`	`getStatusDetail(boolean multiline)` Returns detailed status, suitable for a hover.
`java.lang.String`	`getStatusSummary()`
`Task<?>`	`getSubmittedByTask()` task which submitted this task, if was submitted by a task
`long`	`getSubmitTimeUtc()` if `isSubmitted()` returns the time when the task was submitted; or -1 otherwise
`java.util.Set<java.lang.Object>`	`getTags()`
`java.lang.Thread`	`getThread()` The thread where the task is running, if it is running.
`T`	`getUnchecked()` As `Future.get()`, but propagating checked exceptions as unchecked for convenience.
`T`	`getUnchecked(Duration duration)` As `Future.get()`, but propagating checked exceptions as unchecked for convenience (including a `TimeoutException` if the duration expires)
`boolean`	`isBegun()` Whether task has started running.
`boolean`	`isError()` Whether the task threw an error, including cancellation (implies `Future.isDone()`)
`boolean`	`isSubmitted()` Whether task has been submitted Submitted tasks are normally expected to start running then complete, but unsubmitted tasks are sometimes passed around for someone else to submit them.

Methods inherited from interface com.google.common.util.concurrent.ListenableFuture
addListener

Methods inherited from interface java.util.concurrent.Future
get, get, isCancelled, isDone

Methods inherited from interface brooklyn.management.TaskAdaptable
asTask

- Method Detail
  - getId
```
java.lang.String getId()
```
  - getTags
```
java.util.Set<java.lang.Object> getTags()
```
  - getSubmitTimeUtc
```
long getSubmitTimeUtc()
```
    if isSubmitted() returns the time when the task was submitted; or -1 otherwise
  - getStartTimeUtc
```
long getStartTimeUtc()
```
    if isBegun() returns the time when the task was starts; guaranteed to be >= getSubmitTimeUtc() > 0 if started, or -1 otherwise
  - getEndTimeUtc
```
long getEndTimeUtc()
```
    if Future.isDone() (for any reason) returns the time when the task ended; guaranteed to be >= getStartTimeUtc() > 0 if ended, or -1 otherwise
  - getDisplayName
```
java.lang.String getDisplayName()
```
  - getDescription
```
java.lang.String getDescription()
```
  - getSubmittedByTask
```
Task<?> getSubmittedByTask()
```
    task which submitted this task, if was submitted by a task
  - getThread
```
java.lang.Thread getThread()
```
    The thread where the task is running, if it is running.
  - isSubmitted
```
boolean isSubmitted()
```
    Whether task has been submitted Submitted tasks are normally expected to start running then complete, but unsubmitted tasks are sometimes passed around for someone else to submit them.
  - isBegun
```
boolean isBegun()
```
    Whether task has started running. Will remain true after normal completion or non-cancellation error. will be true on cancel iff the thread did actually start.
  - isError
```
boolean isError()
```
    Whether the task threw an error, including cancellation (implies Future.isDone())
  - blockUntilStarted
```
void blockUntilStarted()
```
    Causes calling thread to block until the task is started.
  - blockUntilEnded
```
void blockUntilEnded()
```
    Causes calling thread to block until the task is ended.
    Either normally or by cancellation or error, but without throwing error on cancellation or error. (Errors are logged at debug.)
  - blockUntilEnded
```
boolean blockUntilEnded(Duration timeout)
```
    As blockUntilEnded(), but returning after the given timeout; true if the task has ended and false otherwise
  - getStatusSummary
```
java.lang.String getStatusSummary()
```
  - getStatusDetail
```
java.lang.String getStatusDetail(boolean multiline)
```
    Returns detailed status, suitable for a hover. Plain-text format, with new-lines (and sometimes extra info) if multiline enabled.
  - get
```
T get(Duration duration)
      throws java.lang.InterruptedException,
             java.util.concurrent.ExecutionException,
             java.util.concurrent.TimeoutException
```
    As Future.get(long, java.util.concurrent.TimeUnit)
    
    Throws:
    
    java.lang.InterruptedException
    
    java.util.concurrent.ExecutionException
    
    java.util.concurrent.TimeoutException
  - getUnchecked
```
T getUnchecked()
```
    As Future.get(), but propagating checked exceptions as unchecked for convenience.
  - getUnchecked
```
T getUnchecked(Duration duration)
```
    As Future.get(), but propagating checked exceptions as unchecked for convenience (including a TimeoutException if the duration expires)
  - cancel
```
boolean cancel(boolean mayInterruptIfRunning)
```
    As Future.cancel(boolean). Note that Future.isDone() and blockUntilEnded(Duration) return immediately once a task is cancelled, consistent with the underlying FutureTask behaviour. TODO Fine-grained control over underlying jobs, e.g. to ensure anything represented by this task is actually completed, is not (yet) publicly exposed. See the convenience method blockUntilInternalTasksEnded in the Tasks set of helpers for more discussion.
    
    Specified by:
    
    cancel in interface java.util.concurrent.Future<T>

Interface Task<T>

Method Summary

Methods inherited from interface com.google.common.util.concurrent.ListenableFuture

Methods inherited from interface java.util.concurrent.Future

Methods inherited from interface brooklyn.management.TaskAdaptable

Method Detail

getId

getTags

getSubmitTimeUtc

getStartTimeUtc

getEndTimeUtc

getDisplayName

getDescription

getSubmittedByTask

getThread

isSubmitted

isBegun

isError

blockUntilStarted

blockUntilEnded

blockUntilEnded

getStatusSummary

getStatusDetail

get

getUnchecked

getUnchecked

cancel