Class WorkerTask

Method Details

• run

  public abstract ReturnState run()

  Processes the work that the task has to do. The task doesn't necessarily run to completion in one go - it's likely that the task will run out of input or output first, so it'll need to keep coming back and chipping away at the work.

• runPublic

  public ReturnState runPublic()

• getPageReader

  public Optional<PageReader> getPageReader()

  Returns an optional helper for reading pages of input Tuples from the ReadPageBuffer (note that not all tasks have an input buffer though).

• getPageWriter

  public Optional<PageWriter> getPageWriter()

  Returns an optional helper for writing pages of output Tuples to the WritePageBuffer (note that not all tasks have an output buffer though).

• hasInputPage

  protected boolean hasInputPage()

• hasOutputPage

  protected boolean hasOutputPage()

• hasPageInProgress

  public boolean hasPageInProgress()

  Returns true if the task currently has a page of either input or output that it hasn't finished with yet.

• isInputReady

  public final boolean isInputReady()

  Test for whether this task should run based on the state of the input buffer. Note that because of an awkward case in the scheduling logic, this method will return true if there are no tuples but the input buffer has been marked as complete. This allows the task to run once more and be run to completion. This is something we should probably be handling in the scheduler logic instead of this test.

  Returns:

  true if there are tuples in the input buffer to be read, or an incomplete page, or the input buffer has been marked as complete.

• isOutputReady

  public final boolean isOutputReady()

  Test for whether this task should run based on the state of the output buffer.

  It will ignore the state of the output buffer if there's no more input - but this check may disappear once we have better test coverage and can confirm it's not relied upon. If it is, it should be in a task specific check.

  Returns:

  true if there is capacity in the output or the input is complete

• isReadyToRun

  public boolean isReadyToRun()

  Returns true if the task has work it can do. Returns false if the task is blocked waiting on either more input, more output buffers to free up, or it's dependent on other tasks that haven't completed yet.

• taskComplete

  protected ReturnState taskComplete()

• getLastStep

  public nz.org.riskscape.engine.pipeline.RealizedStep getLastStep()

• getFirstStep

  public nz.org.riskscape.engine.pipeline.RealizedStep getFirstStep()

• getFirstStepRealizedResult

  protected nz.org.riskscape.engine.pipeline.Realized getFirstStepRealizedResult()

• toString

  public String toString()

  Overrides:

  toString in class Object

• close

  public void close()

  Override this method to clean up any resources that were allocated/created by this task for use during execution. Will be called from the scheduler once the task has signaled it is complete, but it may also get called if a job that this task was part of has failed.

  Thread safety should be ensured by requiring the scheduler to only call close on a task that is not currently being run.

  Implementations shouldn't need to do any buffer management in this method, it's meant for closing things like TupleIterators or other sorts of resources that follow the Closeable pattern.

  Specified by:

  close in interface AutoCloseable

• isCreated

  public boolean isCreated()

• isStarted

  public boolean isStarted()

• isComplete

  public boolean isComplete()

• getName

  public final String getName()

  Returns:

  a unique name for this worker task, based on the step(s) it covers, and the type of worker it is.

• getSpecNameBrief

  public String getSpecNameBrief()

  Returns:

  a unique name for the worker's TaskSpec that is brief and user-friendly. This can be used as a simple way to represent the work that this task is doing to the user.

• producesResult

  public abstract boolean producesResult()

• consumeProcessingResult

  public Object consumeProcessingResult()

  Returns:

  a processingResult that has been set, clearing its value in the process (to allow the result to be garbage collected in the fullness of time)

• markStarted

  public void markStarted()

• markComplete

  public void markComplete()

• getSpec

  public TaskSpec getSpec()

• getContext

  public nz.org.riskscape.engine.pipeline.ExecutionContext getContext()