software.amazon.awssdk.crt.io

Class EventLoopGroup

java.lang.Object

software.amazon.awssdk.crt.CrtResource

software.amazon.awssdk.crt.io.EventLoopGroup

All Implemented Interfaces:

AutoCloseable

public final class EventLoopGroup
extends CrtResource

This class wraps the aws_event_loop_group from aws-c-io to provide access to an event loop for the MQTT protocol stack in the AWS Common Runtime.

Nested Class Summary

Nested classes/interfaces inherited from class software.amazon.awssdk.crt.CrtResource

CrtResource.ResourceInstance

Constructor Summary

Constructors

Constructor and Description
EventLoopGroup(int numThreads) Creates a new event loop group for the I/O subsystem to use to run non-blocking I/O requests
EventLoopGroup(int cpuGroup, int numThreads) Creates a new event loop group for the I/O subsystem to use to run non-blocking I/O requests.

Method Summary

Modifier and Type	Method and Description
protected boolean	canReleaseReferencesImmediately() Determines whether a resource releases its dependencies at the same time the native handle is released or if it waits.
static void	closeStaticDefault() Closes the static default event loop group, if it exists.
CompletableFuture<Void>	getShutdownCompleteFuture()
protected void	releaseNativeHandle() Stops the event loop group's tasks and frees all resources associated with the the group.
static void	setStaticDefaultNumThreads(int numThreads) Sets the number of threads for the static default event loop group, should it ever be created.

Methods inherited from class software.amazon.awssdk.crt.CrtResource

acquireNativeHandle, addRef, addReferenceTo, close, collectNativeResource, collectNativeResources, decRef, getNativeHandle, getResourceLogDescription, isNull, logNativeResources, releaseReferences, removeReferenceTo, setDescription, swapReferenceTo, waitForNoResources

Methods inherited from class java.lang.Object

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

Constructor Detail

EventLoopGroup

public EventLoopGroup(int numThreads)
               throws CrtRuntimeException

Creates a new event loop group for the I/O subsystem to use to run non-blocking I/O requests

Parameters:

numThreads - The number of threads that the event loop group may run tasks across. Usually 1.

Throws:

CrtRuntimeException - If the system is unable to allocate space for a native event loop group

EventLoopGroup

public EventLoopGroup(int cpuGroup,
                      int numThreads)
               throws CrtRuntimeException

Creates a new event loop group for the I/O subsystem to use to run non-blocking I/O requests. When using this constructor, the threads will be pinned to a particular cpuGroup (e.g. a particular NUMA node).

Parameters:

cpuGroup - the index of the cpu group to bind to (for example NUMA node 0 would be 0, NUMA node 1 would be 1 etc...)

numThreads - The number of threads that the event loop group may run tasks across. Usually 1.

Throws:

CrtRuntimeException - If the system is unable to allocate space for a native event loop group

Method Detail

canReleaseReferencesImmediately

protected boolean canReleaseReferencesImmediately()

Determines whether a resource releases its dependencies at the same time the native handle is released or if it waits. Resources that wait are responsible for calling releaseReferences() manually.

Specified by:

canReleaseReferencesImmediately in class CrtResource

Returns:

true if this resource releases synchronously, false if this resource performs async shutdown

releaseNativeHandle

protected void releaseNativeHandle()

Stops the event loop group's tasks and frees all resources associated with the the group. This should be called after all other clients/connections and other resources are cleaned up, or else they will not clean up completely.

Specified by:

releaseNativeHandle in class CrtResource

getShutdownCompleteFuture

public CompletableFuture<Void> getShutdownCompleteFuture()

setStaticDefaultNumThreads

public static void setStaticDefaultNumThreads(int numThreads)

Sets the number of threads for the static default event loop group, should it ever be created. Has no effect if the static default event loop group has already been created.

Parameters:

numThreads - number of threads for the static default event loop group

closeStaticDefault

public static void closeStaticDefault()

Closes the static default event loop group, if it exists. Primarily intended for tests that use the static default event loop group, before they call waitForNoResources().