de.caff.util.concurrent

Interface PriorityExecutor

All Known Implementing Classes:

PriorityThreadPoolExecutor

public interface PriorityExecutor

Executor which executes a task with a given priority. On heavy load situations it is possible that low priority tasks starve depending on the implementation of the executor.

Author:

Rammi

Field Summary

Fields

Modifier and Type	Field and Description
static int	CANT_REMOVE Return value for removeTasksWithMark(Object) if removing is not supported.
static PriorityExecutor	DIRECT_EXECUTOR Priority executor which just executes the task directly without caring for priority.
static long	NO_ID Return value for execute(Priority, Object, Runnable) indicating no valid id.

Method Summary

Modifier and Type	Method and Description
long	execute(Priority priority, java.lang.Object mark, java.lang.Runnable task) Execute a task with the given priority.
long	executeWithLifeCycle(Priority priority, TaskLifeCycleListener mark, java.lang.Runnable task) Execute a task with the given priority.
int	removeTasksWithMark(java.lang.Object mark) Remove all tasks which where started with the given mark.
boolean	removeTaskWithId(long id) Remove the task with the given id.

Field Detail

NO_ID

static final long NO_ID

Return value for execute(Priority, Object, Runnable) indicating no valid id.

See Also:

Constant Field Values

CANT_REMOVE

static final int CANT_REMOVE

Return value for removeTasksWithMark(Object) if removing is not supported.

See Also:

Constant Field Values

DIRECT_EXECUTOR

static final PriorityExecutor DIRECT_EXECUTOR

Priority executor which just executes the task directly without caring for priority. As there is no queue, it neither cares for priority nor for mark.

Method Detail

execute

long execute(@NotNull
             Priority priority,
             @Nullable
             java.lang.Object mark,
             @NotNull
             java.lang.Runnable task)

Execute a task with the given priority.

Parameters:

priority - priority of task

mark - mark which allows access to objects in queue. Not all implementation need to take care of this.

task - task to run

Returns:

an id allowing later access to this task, or NO_ID if access is no longer possible

executeWithLifeCycle

long executeWithLifeCycle(@NotNull
                          Priority priority,
                          @NotNull
                          TaskLifeCycleListener mark,
                          @NotNull
                          java.lang.Runnable task)

Execute a task with the given priority.

Parameters:

priority - priority of task

mark - mark which allows access to objects in queue, and also gets informed when the task is enqueued, started and finished. Not all implementation need to take care of this.

task - task to run

Returns:

an id allowing later access to this task, or NO_ID if access is no longer possible

removeTasksWithMark

int removeTasksWithMark(@NotNull
                        java.lang.Object mark)

Remove all tasks which where started with the given mark.

Parameters:

mark - mark to check for

Returns:

number of removed tasks if removing was possibe, or CANT_REMOVE if the executor does not allow removing

removeTaskWithId

boolean removeTaskWithId(long id)

Remove the task with the given id.

Parameters:

id - id

Returns:

true if a rask with the given id was found and removed
false: if none was found