Package de.aristaflow.adept2.core.runtimemanager.executionenvironments

Class ExecutionEnvironment

    • Field Detail

      • SUSPEND_SAVEPOINT

        public static final String SUSPEND_SAVEPOINT
        The name of the savepoint that will be used to store the state of the environment when suspending.
        See Also:
        Constant Field Values

      • logger

        protected Logger logger
        The logger for execution environments. It is protected for extensibility. Note that this will not be set until initialised.

      • activityInstance

        protected final ActivityInstance activityInstance
        The activity (instance) which is encapsulated by this execution environment.

      • localisedActInst

        protected ActivityInstance localisedActInst
        The localised activity (instance) which is encapsulated by this execution environment.

      • sessionContext

        protected SessionContext sessionContext
        The session context for this execution.

      • actData

        protected ActivityData actData
        The activity instance and data context wrapper for this execution. When setting this explicitly, add it it to the cleanup.

      • cleanup

        protected final Cleanup<RuntimeException> cleanup
        The clean-up called after as post-mortem action of this ExecutionEnvironment. Since this is the same logic, it is also used by cleanup().

    • Constructor Detail

      • ExecutionEnvironment

        public ExecutionEnvironment​(ActivityInstance activityInstance)
        Creates a new ExecutionEnvironment for the designated activity. The constructor just sets the activity and the logger.
        Parameters:
        activityInstance - The activity instance for this ExecutionEnvironment.

    • Method Detail

      • init

        public void init​(SessionContext sessContext)
        Initialises this ExecutionEnvironment by setting the session context, the logger field and the activity data. These fields are not available before! Therefore you should call this method very early when initialising or initialising for resume.

        Initialises and prepares the execution of the application and provides all necessary data which maybe necessary for this. This method or ExecutableComponent.initResume(String, SessionContext) is only called once in the lifetime of an executable component. One of these methods is guaranteed to be called before calling any other method.

        When leaving this method the execution has to be completely prepared. This includes for instance the availability of the GUI in the GUI context, which is necessary for Web applications with HTML-UI.

        Specified by:
        init in interface ExecutableComponent
        Parameters:
        sessContext - The session context to associate with this ExecutionEnvironment.

      • initResume

        public void initResume​(String savepointId,
                       SessionContext sessContext)
        Does nothing - overwrite this method to support resuming.
        Note that this does neither set the session context nor the logger.

        Initialises and prepares the resuming of the application and provides all necessary data which maybe necessary for this. This method or ExecutableComponent.init(SessionContext) is only called once in the lifetime of an executable component. One of these methods is guaranteed to be called before calling any other method.

        When leaving this method the execution has to be completely prepared for resuming. That is, the state of the application has to be restored. This includes the GUI.

        Usually this method will delegate also call ExecutableComponent.init(SessionContext).

        Specified by:
        initResume in interface ExecutableComponent
        Parameters:
        savepointId - The identifier of the savepoint at which the application should resume. This must not be null, but it may be the empty string.
        sessContext - The session context in which the component is to be executed.

      • createActivityData

        protected ActivityData createActivityData​(ActivityInstance actInst,
                                          DataContext dataCont,
                                          Logger adLogger)
        Creates new activity data based on the designated information. Override this factory method if you need to override ActivityData. This method will usually be called just once in an early initialisation phase of an execution environment.
        Parameters:
        actInst - The activity (instance) which is encapsulated by this execution environment.
        dataCont - The context providing the activity data.
        adLogger - The logger for logging messages having additional information in case of problems when handling parameters or configuration values.
        Returns:
        The newly created activity data. The caller is responsible for closing.

      • run

        public abstract void run()
        Description copied from interface: ExecutableComponent
        Resembles Runnable.run() except that this method is expected to throw exceptions indicating that the environment was unexpected or an internal failure occurred. Both exceptions as well as RuntimeException will set the corresponding process activity to FAILED.
        Specified by:
        run in interface ExecutableComponent

      • close

        public boolean close()
        Returns false - overwrite this method to support closing.

        Instructs the component to terminate. Within this method the component should deallocate all allocated resources.

        Specified by:
        close in interface ExecutableComponent
        Returns:
        false

      • suspend

        public boolean suspend()
        Returns false - overwrite this method to support suspending.

        Instructs the component to store its internal state to the data context and to terminate at once. The application should be able to continue its job later when resuming.

        Specified by:
        suspend in interface ExecutableComponent
        Returns:
        false

      • kill

        public boolean kill()
        Returns false - overwrite this method to support killing.

        Enforces the application to abort its execution at once. In the case of running a internal transaction application should abort the transaction and should rollback. Within this method the component should deallocate all allocated resources.

        Specified by:
        kill in interface ExecutableComponent
        Returns:
        false

      • prepareCommit

        public Vote prepareCommit()
                   throws IsNotSupportedException
        Throws an IsNotSupportedException - overwrite this method to support Two-phase-commit.

        Instructs the component to vote for Commit or Abort of the distributed transaction it participates in and to prepare a commit.

        Specified by:
        prepareCommit in interface ExecutableComponent
        Returns:
        Nothing, since an IsNotSupportedException is always thrown.
        Throws:
        IsNotSupportedException - This exception is always thrown.

      • rollback

        public boolean rollback()
                 throws IsNotSupportedException
        Throws an IsNotSupportedException - overwrite this method to support rolling back.

        Instructs the component to undo all its modifications done within the current transaction. This method has to be implemented in case the application is resettable.

        Specified by:
        rollback in interface ExecutableComponent
        Returns:
        Nothing, since an IsNotSupportedException is always thrown.
        Throws:
        IsNotSupportedException - This exception is always thrown.

      • getApplicationState

        protected Serializable getApplicationState()
                                    throws IOException
        Gets the application state stored for last savepoint as object. Note that this will only work, if you used setApplicationState(Serializable) or setApplicationState(String, Serializable) for storing the application state.
        Returns:
        An object representing the application state for the last savepoint. This will be null in case no application state has been stored for the last savepoint (and of course if null has been explicitly stored for the last savepoint).
        Throws:
        IOException - If there are problems deserialising the application state, an IOException will be thrown.

      • getRawApplicationState

        protected byte[] getRawApplicationState()
        Gets the raw application state stored for last savepoint. Note that this will only work, if you used setRawApplicationState(byte[]) or setRawApplicationState(String, byte[]) for storing the application state.
        Returns:
        The raw application state for the last savepoint. This will be null in case no application state has been stored for the last savepoint (and of course if null has been explicitly stored for the last savepoint).

      • getApplicationState

        protected Serializable getApplicationState​(String savepoint)
                                    throws IOException
        Gets the application state stored for the designated savepoint as object. Note that this will only work, if you used setApplicationState(String, Serializable) for storing the application state.
        Parameters:
        savepoint - The name of the savepoint for which to retrieve the application state. This allows for several different application states.
        Returns:
        An object representing the application state for the designated savepoint. This will be null in case no application state has been stored for the designated savepoint (and of course if null has been explicitly stored for the designated savepoint).
        Throws:
        IOException - If there are problems deserialising the application state, an IOException will be thrown.

      • getRawApplicationState

        protected byte[] getRawApplicationState​(String savepoint)
        Gets the raw application state stored for designated savepoint as object. Note that this will only work, if you used setRawApplicationState(byte[]) or setRawApplicationState(String, byte[]) for storing the application state.
        Parameters:
        savepoint - The name of the savepoint for which to retrieve the raw application state. This allows for several different application states.
        Returns:
        The raw application state for the designated savepoint. This will be null in case no application state has been stored for the designated savepoint (and of course if null has been explicitly stored for the designated savepoint).

      • setApplicationState

        protected void setApplicationState​(Serializable appState)
                            throws IOException
        Stores the application state as serialised Java object for the next savepoint. Use null to remove the state for the next savepoint.
        Parameters:
        appState - An object representing the application state for the next savepoint. Use null to remove it for the next savepoint.
        Throws:
        IOException - If there are problems serialising the application state, an IOException will be thrown.
        See Also:
        RuntimeEnvironment.setApplicationState(byte[])

      • setRawApplicationState

        protected void setRawApplicationState​(byte[] appState)
        Stores the raw application state for the next savepoint. Use null to remove the state for the next savepoint.
        Parameters:
        appState - The raw application state for the next savepoint. Use null to remove it for the next savepoint.
        See Also:
        RuntimeEnvironment.setApplicationState(byte[])

      • setApplicationState

        protected void setApplicationState​(String savepoint,
                                   Serializable appState)
                            throws IOException
        Stores the application state for the designated savepoint as object. Use null to remove the designated savepoint. The savepoint will not be flushed.
        Parameters:
        savepoint - The savepoint for which to store the application state. This allows for several different application states.
        appState - An object representing the application state for the designated savepoint. Use null to remove the designated savepoint.
        Throws:
        IOException - If there are problems serialising the application state, an IOException will be thrown.
        See Also:
        RuntimeEnvironment.setApplicationState(byte[]), RuntimeEnvironment.setSavepoint(String, boolean)

      • setRawApplicationState

        protected void setRawApplicationState​(String savepoint,
                                      byte[] appState)
        Stores the raw application state for the designated savepoint. Use null to remove the state for the designated savepoint. The savepoint will not be flushed.
        Parameters:
        savepoint - The savepoint for which to store the application state. This allows for several different application states.
        appState - The raw application state for the designated savepoint. Use null to remove it for the designated savepoint.
        See Also:
        RuntimeEnvironment.setApplicationState(byte[])

      • requireGUIContext

        protected <T extends GUIContext> T requireGUIContext​(Class<T> guiContextType)
        Returns the required GUI context or throws an exception if it is not available.
        Type Parameters:
        T - the type of the required GUI context
        Parameters:
        guiContextType - the type of the required GUI context
        Returns:
        the required GUI context if available
        Throws:
        ApplicationEnvironmentException - if the required GUI context is not available