org.jtrim2.executor

Interface CancelableFunction<V>

Type Parameters:

V - the type of the result of the CancelableFunction

public interface CancelableFunction<V>

Defines a task which can return an object and be canceled through a CancellationToken. There is no constraint on what an implementation of CancelableFunction may do, it must implement its sole execute method do whatever task it wishes.

How a task must respond to cancellation requests is implementation dependent but it may always terminate by throwing an OperationCanceledException.

Thread safety

The thread-safety property of CancelableFunction is completely implementation dependent, so in general they does not need to be thread-safe.

Synchronization transparency

CancelableFunction is not required to be synchronization transparent.

See Also:

CancelableTask, TaskExecutorService

Method Summary

Modifier and Type	Method and Description
V	execute(CancellationToken cancelToken) Executes the the implementation dependent task and returns the result of the computation.

Method Detail

execute

V execute(CancellationToken cancelToken)
   throws Exception

Executes the the implementation dependent task and returns the result of the computation. The task may check periodically the specified CancellationToken to detect cancellation requests and return immediately or throw an OperationCanceledException.

Parameters:

cancelToken - the CancellationToken which can be checked periodically by this task to detect cancellation requests. This argument cannot be null.

Returns:

the result of the computation. This method may return null.

Throws:

OperationCanceledException - thrown if the task detects that it was canceled (usually by checking the provided CancellationToken)

Exception - tasks may throw an exception they cannot handle. The executor should usually log these exceptions as severe problems.