Package io.github.classgraph.utils

Class WorkQueue<T>

java.lang.Object

io.github.classgraph.utils.WorkQueue<T>

Type Parameters:

T - The work unit type.

All Implemented Interfaces:

AutoCloseable

public class WorkQueue<T>
extends Object
implements AutoCloseable

A parallel work queue.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static interface	WorkQueue.WorkQueuePreStartHook<T>	A hook that is called once a WorkQueue is created, inside its try-with-resources block, before the workers are started.
static interface	WorkQueue.WorkUnitProcessor<T>	A work unit processor.

Method Summary

Modifier and Type	Method	Description
void	addWorkUnits(Collection<T> workUnits)	Add multiple units of work.
void	close()	Ensure that there are no work units still uncompleted.
static <U> void	runWorkQueue(Collection<U> elements, ExecutorService executorService, int numParallelTasks, WorkQueue.WorkUnitProcessor<U> workUnitProcessor, InterruptionChecker interruptionChecker, LogNode log)	Start a work queue on the elements in the provided collection, blocking until all work units have been completed.
static <U> void	runWorkQueue(Collection<U> elements, ExecutorService executorService, int numParallelTasks, WorkQueue.WorkUnitProcessor<U> workUnitProcessor, WorkQueue.WorkQueuePreStartHook<U> workQueuePreStartHook, InterruptionChecker interruptionChecker, LogNode log)	Start a work queue on the elements in the provided collection, blocking until all work units have been completed.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

runWorkQueue

public static <U> void runWorkQueue(Collection<U> elements,
                                    ExecutorService executorService,
                                    int numParallelTasks,
                                    WorkQueue.WorkUnitProcessor<U> workUnitProcessor,
                                    WorkQueue.WorkQueuePreStartHook<U> workQueuePreStartHook,
                                    InterruptionChecker interruptionChecker,
                                    LogNode log)
                             throws ExecutionException,
                                    InterruptedException

Start a work queue on the elements in the provided collection, blocking until all work units have been completed. Calls workQueuePreStartHook with a ref to the work queue before starting the workers.

Type Parameters:

U - The type of the work queue units.

Parameters:

elements - The work queue units to process.

executorService - The ExecutorService.

numParallelTasks - The number of parallel tasks.

workUnitProcessor - The WorkQueue.WorkUnitProcessor.

workQueuePreStartHook - The WorkQueue.WorkQueuePreStartHook.

interruptionChecker - The InterruptionChecker.

log - The log.

Throws:

ExecutionException - If an exception is thrown while processing a work unit.

InterruptedException - If the work was interrupted.

runWorkQueue

public static <U> void runWorkQueue(Collection<U> elements,
                                    ExecutorService executorService,
                                    int numParallelTasks,
                                    WorkQueue.WorkUnitProcessor<U> workUnitProcessor,
                                    InterruptionChecker interruptionChecker,
                                    LogNode log)
                             throws ExecutionException,
                                    InterruptedException

Start a work queue on the elements in the provided collection, blocking until all work units have been completed.

Type Parameters:

U - The type of the work queue units.

Parameters:

elements - The work queue units to process.

executorService - The ExecutorService.

numParallelTasks - The number of parallel tasks.

workUnitProcessor - The WorkQueue.WorkUnitProcessor.

interruptionChecker - The InterruptionChecker.

log - The log.

Throws:

ExecutionException - If an exception is thrown while processing a work unit.

InterruptedException - If the work was interrupted.

addWorkUnits

public void addWorkUnits(Collection<T> workUnits)

Add multiple units of work. May be called by workers to add more work units to the tail of the queue.

Parameters:

workUnits - The work units to add to the tail of the queue.

close

public void close()
           throws ExecutionException

Ensure that there are no work units still uncompleted. This should be called after runWorkLoop() exits on the main thread (e.g. using try-with-resources, since this class is AutoCloseable). If any work units are still uncompleted (e.g. in the case of an exception), will shut down remaining workers.

Specified by:

close in interface AutoCloseable

Throws:

ExecutionException