com.ebay.bascomtask.core

Interface TaskInterface<T>

Type Parameters:

T - identifies that interface that defines task methods

All Known Subinterfaces:

ConsumerTask, SupplierTask<R>

All Known Implementing Classes:

ConsumerTask.ConsumerTask1, ConsumerTask.ConsumerTask2, SupplierTask.SupplierTask0, SupplierTask.SupplierTask1, SupplierTask.SupplierTask2

public interface TaskInterface<T>

Common interface that all user POJO task interfaces must implement in order to be added to an Orchestrator, for example like this:

 interface IDelay implements TaskInterface<IDelay> {
    // Add test methods here
 }

 class Delay implements IDelay {...}
 

Task classes such as Delay or its interface IDelay above can implement/extend other interfaces, but among all of them only one should be designated as argument to TaskInterface in the manner above.

There are no required methods to implement from this interface since all have default implementations. For uncommon cases some of these methods may usefully be overridden as noted in each javadoc. Several convenience methods are also provided for wrapping and unwrapping values in/from CompletableFutures. There use is completely optional.

Author:

Brendan McCarthy

See Also:

Orchestrator.task(TaskInterface)

Method Summary

Modifier and Type	Method and Description
default T	activate() Forces immediate activation of task methods instead of the default behavior which is that task methods are only lazily activated according to the rules described in Orchestrator.task(TaskInterface).
default CompletableFuture<Void>	complete() Convenience method for subclasses that return a void result.
default <R> CompletableFuture<R>	complete(R arg) Convenience method for subclasses that creates a CompletableFuture from a constant value, which may or may not be null.
default <R> R	get(CompletableFuture<R> future) Convenience method for subclasses for accessing a CompletableFuture argument.
default String	getName() Returns the name of this task, useful for logging and profiling.
default boolean	isActivate() Indicates that task methods should be activated immediately.
default boolean	isLight() Indicates the default weight of task methods that do not have a Light annotation.
default boolean	isRunSpawned() Indicates that task methods should have threads spawned for them.
default T	light() Forces inline execution of task methods on this object, i.e.
default T	name(String name) Provides a name for this task, useful for logging and profiling.
default T	runSpawned() Forces a new thread to be allocated for task methods on this class, which can be useful to keep the calling thread free for other purposes.

Method Detail

name

default T name(String name)

Provides a name for this task, useful for logging and profiling. TaskWrappers (as returned by Orchestrator.task(TaskInterface), already support this method which therefore works in expressions like $.task(myTask).name("myTask").myMethod(). That is the typical usage, so there is normally no need to override this method, but subclasses can override if desired to also enable invocation directly on the task, e.g. $.task(myTask.name("myTask")).myMethod()

Parameters:

name - to set

Returns:

this

getName

default String getName()

Returns the name of this task, useful for logging and profiling. Subclasses can optionally override if they want to expose something other than the class name as the default name. Whether or not overridden, any TaskWrapper (the object that is returned by adding a task to an Orchestrator) that wraps this object (there can be more than one) will manage its own name and use this value returned here only if not explicitly set during task wiring.

Returns:

name

light

default T light()

Forces inline execution of task methods on this object, i.e. prevents a new thread from being spawned for them when an Orchestrator might otherwise do so. TaskWrappers (as returned by Orchestrator.task(TaskInterface), already support this method which therefore works in expressions like $.task(myTask).light().myMethod() That is the typical usage, so there is normally no need to override this method, but subclasses can override if desired to also enable invocation directly on the task, e.g. $.task(myTask.light()).myMethod().

This call reverses any previous call to runSpawned(). The impact of this call is redundant for task methods that already have Light annotation.

Returns:

this

isLight

default boolean isLight()

Indicates the default weight of task methods that do not have a Light annotation.

Returns:

true iff by default a thread should never be spawned for task methods on this class

runSpawned

default T runSpawned()

Forces a new thread to be allocated for task methods on this class, which can be useful to keep the calling thread free for other purposes. This overrides the default behavior, which is spawn threads when an single thread finds more than one task ready to fire. TaskWrappers (as returned by Orchestrator.task(TaskInterface), already support this method which therefore works in expressions like $.task(myTask).runSpawned().myMethod(). That is the typical usage, so there is normally no need to override this method, but subclasses can override if desired to also enable invocation directly on the task, e.g. $.task(myTask.runSpawned()).myMethod()

This call reverses any previous call to light(). Its effect is superseded by a Light annotation on a task method if present.

Returns:

this

isRunSpawned

default boolean isRunSpawned()

Indicates that task methods should have threads spawned for them.

Returns:

true iff by default a thread should be spawned for task methods on this class

activate

default T activate()

Forces immediate activation of task methods instead of the default behavior which is that task methods are only lazily activated according to the rules described in Orchestrator.task(TaskInterface). TaskWrappers (as returned by Orchestrator.task(TaskInterface), already support this method which therefore works in expressions like $.task(myTask).activate(true).myMethod(). That is the typical usage, so there is normally no need to override this method, but subclasses can override if desired to also enable invocation directly on the task, e.g. $.task(myTask.activate(true)).myMethod()

Returns:

this

isActivate

default boolean isActivate()

Indicates that task methods should be activated immediately. Subclasses can override to change the default false return value if desired.

Returns:

true iff by default a thread should never be spawned for task methods on this class

get

default <R> R get(CompletableFuture<R> future)

Convenience method for subclasses for accessing a CompletableFuture argument. This attempts to unwrap CompletionExceptions in a more useful than is provided by calling the standard CompletableFuture.join() operation.

Type Parameters:

R - type of value returned

Parameters:

future - to retrieve value from

Returns:

value wrapped by the supplied future, which may or may not be null

complete

default <R> CompletableFuture<R> complete(R arg)

Convenience method for subclasses that creates a CompletableFuture from a constant value, which may or may not be null.

Type Parameters:

R - type of value returned

Parameters:

arg - value to wrap

Returns:

CompletableFuture that wraps the provided value

complete

default CompletableFuture<Void> complete()

Convenience method for subclasses that return a void result. The framework requires a return result even for logically void methods in order to expose common methods (such as being able to start task execution) on the return result.

Returns:

a Void result