Package de.aristaflow.adept2.core.eventmanager.fileevents

Class InstanceStartEventHandler

  • All Implemented Interfaces:
    EventHandler
    @ConfigurationDescription(properties={@Property(name="IsCritical",type=BOOLEAN,defaultValue="true",description="Whether the event handler is critical and problems handling the event should abort all handling of the current event."),,})
public class InstanceStartEventHandler
extends AbstractEventHandler
    An event handler for file events, that stores data from an occurred file event as input parameters in the data container of an instance and starts this instance afterwards.
    The input parameters need to have specific names to allow for setting the values according to the file.

    • Field Detail

      • CONF_IS_CRITICAL

        public static final String CONF_IS_CRITICAL
        Configuration key: Whether the event handler is critical and problems handling the event should abort all handling of the current event.
        See Also:
        Constant Field Values

      • CONF_PROCESS_TYPE

        public static final String CONF_PROCESS_TYPE
        Configuration key: The process type of which to start the "latest" template in case the appropriate event occurs.
        See Also:
        Constant Field Values

      • processType

        protected final String processType
        The process type of which to start the "latest" template in case the appropriate event occurs.

      • template

        protected TemplateReference template
        The template which to instantiate in case an appropriate mail event occurs. This will be temporarily set to null if there are problems instantiating it.

      • eventManager

        protected final AbstractEventManager eventManager
        The event manager for communicating with the runtime service.

      • PARAM_MODIFIED_DATE

        public static final String PARAM_MODIFIED_DATE
        Process parameter name for the file name.
        See Also:
        Constant Field Values

      • PARAM_LOCK_FILE

        public static final String PARAM_LOCK_FILE
        Process parameter name for the lock file.
        See Also:
        Constant Field Values

    • Constructor Detail

      • InstanceStartEventHandler

        public InstanceStartEventHandler​(org.apache.commons.configuration2.Configuration conf,
                                 AbstractEventManager eventManager,
                                 Registry registry)
                          throws ConfigurationException
        Creates a new handler for file events that starts instances and stores data from the file in the instance input parameters.
        Parameters:
        conf - The configuration for this plugin instance.
        eventManager - The event manager for starting the process instance.
        registry - The registry for retrieving the plugin instance name (handler ID).
        Throws:
        ConfigurationException - If there are problems creating the configured file store or writing to it or the template cannot be retrieved or has the wrong input parameter, a ConfigurationException will be thrown.

    • Method Detail

      • handleEvent

        public boolean handleEvent​(Event eve,
                           boolean consumed)
                    throws EventHandlingException
        Description copied from interface: EventHandler
        This method actually processes an event. What is done depends on the implementation of the event handler. Some restrictions may apply depending on the produced event. Only events will be received for which the event handler is registered. However, to improve robustness, an event handler should check the event before processing. If it cannot handle the provided event, this method should just return.
        Event handling is usually synchronously, that is, this method will only be executed by one thread at a time. If another event of the same type occurs while still handling the previous event, the second event will be suspended until the previous event has been completely handled. There is no need to start a separate thread while handling to improve performance. But it is not forbidden to do so. Handling that takes place in a new thread is not exclusive any more and therefore must not consume the event!
        Parameters:
        eve - The event that occurred and for which this event handler is registered.
        consumed - Whether the event has been consumed by a previous event handler.
        Returns:
        Whether the event has been consumed (that is changed) while handling it. If the event has been consumed before the current handing, it will have to remain consumed (implementations must return true).
        Throws:
        EventHandlingException - If there have been problems handling the event, an EventHandlingException may be thrown. If this is critical, the event handling for the current event will stop. If it is non-critical, other event handlers will also get the event for handling it.
        If event handling fails, the corresponding event handler needs to roll back its changes, especially a consuming event handler.

      • getAndCheckTemplate

        protected TemplateReference getAndCheckTemplate​(SessionToken session)
                                         throws InvalidDataTypeException,
                                                NoSuchParameterException
        Retrieves the "latest" template of the configured process type and checks for whether it has the right input parameter. An input parameter having the right name for a file event must be of the right data type and there must not be any mandatory input parameter that do not have an appropriate file event name.
        Parameters:
        session - The session token used to retrieve the "latest" template.
        Returns:
        The "latest" template of the configured process type or null in case the process type does not have a template.
        Throws:
        InvalidDataTypeException - If the template has an input parameter mapping to a file event (due to its name) but has the wrong type, an InvalidDataTypeException will be thrown.
        NoSuchParameterException - If the template has a mandatory input parameter that does not map to a file event, a NoSuchParameterException will be thrown.

      • processFileEvent

        protected void processFileEvent​(FileEvent event,
                                Collection<? extends Parameter> inParams,
                                InstanceDataContainer dataContainer)
                         throws InvalidDataTypeException,
                                NoSuchParameterException,
                                IOException
        Processes the file of the designated event and sets the values of the input parameters in the designated data container.
        Parameters:
        event - The event which to process and which provides the values for the input parameters.
        inParams - The input parameters of the template.
        dataContainer - The data container of the template in which to set the values.
        Throws:
        InvalidDataTypeException - If writing to the data container fails due to a provided input parameter having another type in the data container or a parameter has a wrong user-defined type, an InvalidDataTypeException will be thrown.
        NoSuchParameterException - If writing to the data container fails due to a provided input parameter not being in the data container, a NoSuchParameterException will be thrown.
        IOException - If creating the value for an UDT fails, an IOException will be thrown.