Package org.camunda.bpm.engine.impl

Class ExternalTaskServiceImpl

java.lang.Object
org.camunda.bpm.engine.impl.ServiceImpl
org.camunda.bpm.engine.impl.ExternalTaskServiceImpl
All Implemented Interfaces:
ExternalTaskService
public class ExternalTaskServiceImpl extends ServiceImpl implements ExternalTaskService
Author:
Thorben Lindhauer, Christopher Zell, Askar Akhmerov

  • Constructor Details

    • ExternalTaskServiceImpl

      public ExternalTaskServiceImpl()

  • Method Details

    • fetchAndLock

      public ExternalTaskQueryBuilder fetchAndLock(int maxTasks, String workerId)
      Description copied from interface: ExternalTaskService
      Calls method fetchAndLock(maxTasks, workerId, usePriority), where usePriority is false.
      Specified by:
      fetchAndLock in interface ExternalTaskService
      Parameters:
      maxTasks - the maximum number of tasks to return
      workerId - the id of the worker to lock the tasks for
      Returns:
      a builder to define and execute an external task fetching operation

    • fetchAndLock

      public ExternalTaskQueryBuilder fetchAndLock(int maxTasks, String workerId, boolean usePriority)
      Description copied from interface: ExternalTaskService

      Defines fetching of external tasks by using a fluent builder. The following parameters must be specified: A worker id, a maximum number of tasks to fetch and a flag that indicates whether priority should be regarded or not. The builder allows to specify multiple topics to fetch tasks for and individual lock durations. For every topic, variables can be fetched in addition. If priority is enabled, the tasks with the highest priority are fetched.

      Returned tasks are locked for the given worker until now + lockDuration expires. Locked tasks cannot be fetched or completed by other workers. When the lock time has expired, a task may be fetched and locked by other workers.

      Returns at most maxTasks tasks. The tasks are arbitrarily distributed among the specified topics. Example: Fetching 10 tasks of topics "a"/"b"/"c" may return 3/3/4 tasks, or 10/0/0 tasks, etc.

      May return less than maxTasks tasks, if there exist not enough unlocked tasks matching the provided topics or if parallel fetching by other workers results in locking failures.

      Returns only tasks that the currently authenticated user has at least one permission out of all of the following groups for:

      Specified by:
      fetchAndLock in interface ExternalTaskService
      Parameters:
      maxTasks - the maximum number of tasks to return
      workerId - the id of the worker to lock the tasks for
      usePriority - the flag to enable the priority fetching mechanism
      Returns:
      a builder to define and execute an external task fetching operation

    • lock

      public void lock(String externalTaskId, String workerId, long lockDuration)
      Description copied from interface: ExternalTaskService

      Lock an external task on behalf of a worker. Note: Attempting to lock an already locked external task with the same workerId will succeed and a new lock duration will be set, starting from the current moment.

      Specified by:
      lock in interface ExternalTaskService
      Parameters:
      externalTaskId - the id of the external task to lock
      workerId - the id of the worker to lock the task for
      lockDuration - the duration in milliseconds for which task should be locked

    • complete

      public void complete(String externalTaskId, String workerId)
      Description copied from interface: ExternalTaskService

      Completes an external task on behalf of a worker. The given task must be assigned to the worker.

      Specified by:
      complete in interface ExternalTaskService
      Parameters:
      externalTaskId - the id of the external task to complete
      workerId - the id of the worker that completes the task

    • complete

      public void complete(String externalTaskId, String workerId, Map<String,Object> variables)
      Description copied from interface: ExternalTaskService

      Completes an external task on behalf of a worker and submits variables to the process instance before continuing execution. The given task must be assigned to the worker.

      Specified by:
      complete in interface ExternalTaskService
      Parameters:
      externalTaskId - the id of the external task to complete
      workerId - the id of the worker that completes the task
      variables - a map of variables to set on the execution (non-local) the external task is assigned to

    • complete

      public void complete(String externalTaskId, String workerId, Map<String,Object> variables, Map<String,Object> localVariables)
      Description copied from interface: ExternalTaskService

      Completes an external task on behalf of a worker and submits variables to the process instance before continuing execution. The given task must be assigned to the worker.

      Specified by:
      complete in interface ExternalTaskService
      Parameters:
      externalTaskId - the id of the external task to complete
      workerId - the id of the worker that completes the task
      variables - a map of variables to set on the execution the external task is assigned to
      localVariables - a map of variables to set on the execution locally

    • handleFailure

      public void handleFailure(String externalTaskId, String workerId, String errorMessage, int retries, long retryDuration)
      Description copied from interface: ExternalTaskService

      Signals that an external task could not be successfully executed. The task must be assigned to the given worker. The number of retries left can be specified. In addition, a timeout can be provided, such that the task cannot be fetched before now + retryTimeout again.

      If retries is 0, an incident with the given error message is created. The incident gets resolved, once the number of retries is increased again.

      Exceptions raised in evaluating expressions of error event definitions attached to the task will be ignored by this method and the event definitions considered as not-matching.

      Specified by:
      handleFailure in interface ExternalTaskService
      Parameters:
      externalTaskId - the id of the external task to report a failure for
      workerId - the id of the worker that reports the failure
      errorMessage - short error message related to this failure. This message can be retrieved via ExternalTask.getErrorMessage() and is used as the incident message in case retries is null. May be null.
      retries - the number of retries left. External tasks with 0 retries cannot be fetched anymore unless the number of retries is increased via API. Must be >= 0.
      retryDuration - the timeout before the task can be fetched again. Must be >= 0.

    • handleFailure

      public void handleFailure(String externalTaskId, String workerId, String errorMessage, String errorDetails, int retries, long retryDuration)
      Description copied from interface: ExternalTaskService

      Signals that an external task could not be successfully executed. The task must be assigned to the given worker. The number of retries left can be specified. In addition, a timeout can be provided, such that the task cannot be fetched before now + retryTimeout again.

      If retries is 0, an incident with the given error message is created. The incident gets resolved, once the number of retries is increased again.

      Exceptions raised in evaluating expressions of error event definitions attached to the task will be ignored by this method and the event definitions considered as not-matching.

      Specified by:
      handleFailure in interface ExternalTaskService
      Parameters:
      externalTaskId - the id of the external task to report a failure for
      workerId - the id of the worker that reports the failure
      errorMessage - short error message related to this failure. This message can be retrieved via ExternalTask.getErrorMessage() and is used as the incident message in case retries is null. May be null.
      errorDetails - full error message related to this failure. This message can be retrieved via ExternalTaskService.getExternalTaskErrorDetails(String) ()}
      retries - the number of retries left. External tasks with 0 retries cannot be fetched anymore unless the number of retries is increased via API. Must be >= 0.
      retryDuration - the timeout before the task can be fetched again. Must be >= 0.

    • handleFailure

      public void handleFailure(String externalTaskId, String workerId, String errorMessage, String errorDetails, int retries, long retryDuration, Map<String,Object> variables, Map<String,Object> localVariables)
      Description copied from interface: ExternalTaskService

      Signals that an external task could not be successfully executed. The task must be assigned to the given worker. The number of retries left can be specified. In addition, a timeout can be provided, such that the task cannot be fetched before now + retryTimeout again.

      If retries is 0, an incident with the given error message is created. The incident gets resolved, once the number of retries is increased again.

      Exceptions raised in evaluating expressions of error event definitions attached to the task will be ignored by this method and the event definitions considered as not-matching.

      Variables passed with the variables or localVariables parameter will be set before any output mapping is performed.
      Specified by:
      handleFailure in interface ExternalTaskService
      Parameters:
      externalTaskId - the id of the external task to report a failure for
      workerId - the id of the worker that reports the failure
      errorMessage - short error message related to this failure. This message can be retrieved via ExternalTask.getErrorMessage() and is used as the incident message in case retries is null. May be null.
      errorDetails - full error message related to this failure. This message can be retrieved via ExternalTaskService.getExternalTaskErrorDetails(String) ()}
      retries - the number of retries left. External tasks with 0 retries cannot be fetched anymore unless the number of retries is increased via API. Must be >= 0.
      variables - a map of variables to set on the execution the external task is assigned to
      localVariables - a map of variables to set on the execution locally

    • handleBpmnError

      public void handleBpmnError(String externalTaskId, String workerId, String errorCode)
      Description copied from interface: ExternalTaskService

      Signals that an business error appears, which should be handled by the process engine. The task must be assigned to the given worker. The error will be propagated to the next error handler. Is no existing error handler for the given bpmn error the activity instance of the external task ends.

      Specified by:
      handleBpmnError in interface ExternalTaskService
      Parameters:
      externalTaskId - the id of the external task to report a bpmn error
      workerId - the id of the worker that reports the bpmn error
      errorCode - the error code of the corresponding bmpn error

    • handleBpmnError

      public void handleBpmnError(String externalTaskId, String workerId, String errorCode, String errorMessage)
      Description copied from interface: ExternalTaskService

      Signals that an business error appears, which should be handled by the process engine. The task must be assigned to the given worker. The error will be propagated to the next error handler. Is no existing error handler for the given bpmn error the activity instance of the external task ends.

      Specified by:
      handleBpmnError in interface ExternalTaskService
      Parameters:
      externalTaskId - the id of the external task to report a bpmn error
      workerId - the id of the worker that reports the bpmn error
      errorCode - the error code of the corresponding bmpn error
      errorMessage - the error message of the corresponding bmpn error

    • handleBpmnError

      public void handleBpmnError(String externalTaskId, String workerId, String errorCode, String errorMessage, Map<String,Object> variables)
      Description copied from interface: ExternalTaskService

      Signals that an business error appears, which should be handled by the process engine. The task must be assigned to the given worker. The error will be propagated to the next error handler. Is no existing error handler for the given bpmn error the activity instance of the external task ends.

      Specified by:
      handleBpmnError in interface ExternalTaskService
      Parameters:
      externalTaskId - the id of the external task to report a bpmn error
      workerId - the id of the worker that reports the bpmn error
      errorCode - the error code of the corresponding bmpn error
      errorMessage - the error message of the corresponding bmpn error
      variables - the variables to pass to the execution

    • unlock

      public void unlock(String externalTaskId)
      Description copied from interface: ExternalTaskService
      Unlocks an external task instance.
      Specified by:
      unlock in interface ExternalTaskService
      Parameters:
      externalTaskId - the id of the task to unlock

    • setRetries

      public void setRetries(String externalTaskId, int retries, boolean writeUserOperationLog)

    • setPriority

      public void setPriority(String externalTaskId, long priority)
      Description copied from interface: ExternalTaskService
      Sets the priority for an external task.
      Specified by:
      setPriority in interface ExternalTaskService
      Parameters:
      externalTaskId - the id of the task to set the
      priority - the new priority of the task

    • createExternalTaskQuery

      public ExternalTaskQuery createExternalTaskQuery()
      Description copied from interface: ExternalTaskService

      Queries for tasks that the currently authenticated user has at least one of the following permissions for:

      Specified by:
      createExternalTaskQuery in interface ExternalTaskService
      Returns:
      a new ExternalTaskQuery that can be used to dynamically query for external tasks.

    • getTopicNames

      public List<String> getTopicNames()
      Description copied from interface: ExternalTaskService
      Returns a list of distinct topic names of all currently existing external tasks. Returns an empty list if no topics are found.
      Specified by:
      getTopicNames in interface ExternalTaskService

    • getTopicNames

      public List<String> getTopicNames(boolean withLockedTasks, boolean withUnlockedTasks, boolean withRetriesLeft)
      Description copied from interface: ExternalTaskService
      Returns a list of distinct topic names of all currently existing external tasks restricted by the parameters. Returns an empty list if no matching tasks are found. Parameters are conjunctive, i.e. only tasks are returned that match all parameters with value true. Parameters with value false are effectively ignored. For example, this means that an empty list is returned if both withLockedTasks and withUnlockedTasks are true.
      Specified by:
      getTopicNames in interface ExternalTaskService
      Parameters:
      withLockedTasks - return only topic names of unlocked tasks
      withUnlockedTasks - return only topic names of locked tasks
      withRetriesLeft - return only topic names of tasks with retries remaining

    • getExternalTaskErrorDetails

      public String getExternalTaskErrorDetails(String externalTaskId)
      Description copied from interface: ExternalTaskService
      Returns the full error details that occurred while running external task with the given id. Returns null when the external task has no error details.
      Specified by:
      getExternalTaskErrorDetails in interface ExternalTaskService
      Parameters:
      externalTaskId - id of the external task, cannot be null.

    • setRetries

      public void setRetries(String externalTaskId, int retries)
      Description copied from interface: ExternalTaskService
      Sets the retries for an external task. If the new value is 0, a new incident with a null message is created. If the old value is 0 and the new value is greater than 0, an existing incident is resolved.
      Specified by:
      setRetries in interface ExternalTaskService
      Parameters:
      externalTaskId - the id of the task to set the

    • setRetries

      public void setRetries(List<String> externalTaskIds, int retries)
      Description copied from interface: ExternalTaskService
      Sets the retries for external tasks. If the new value is 0, a new incident with a null message is created. If the old value is 0 and the new value is greater than 0, an existing incident is resolved.
      Specified by:
      setRetries in interface ExternalTaskService
      Parameters:
      externalTaskIds - the ids of the tasks to set the

    • setRetriesAsync

      public Batch setRetriesAsync(List<String> externalTaskIds, ExternalTaskQuery externalTaskQuery, int retries)
      Description copied from interface: ExternalTaskService
      Sets the retries for external tasks asynchronously as batch. The returned batch can be used to track the progress. If the new value is 0, a new incident with a null message is created. If the old value is 0 and the new value is greater than 0, an existing incident is resolved.
      Specified by:
      setRetriesAsync in interface ExternalTaskService
      Parameters:
      externalTaskIds - the ids of the tasks to set the
      externalTaskQuery - a query which selects the external tasks to set the retries for.
      Returns:
      the batch

    • updateRetries

      public UpdateExternalTaskRetriesSelectBuilder updateRetries()
      Description copied from interface: ExternalTaskService
      Sets the retries for external tasks using a fluent builder. Specify the instances by calling one of the following methods, like externalTaskIds. To set the retries call UpdateExternalTaskRetriesBuilder.set(int) or UpdateExternalTaskRetriesBuilder.setAsync(int).
      Specified by:
      updateRetries in interface ExternalTaskService

    • extendLock

      public void extendLock(String externalTaskId, String workerId, long lockDuration)
      Description copied from interface: ExternalTaskService

      Extends a lock of an external task on behalf of a worker. The given task must be assigned to the worker.

      Specified by:
      extendLock in interface ExternalTaskService
      Parameters:
      externalTaskId - the id of the external task
      workerId - the id of the worker that extends the lock of the task