Module io.helidon.common.configurable

Package io.helidon.common.configurable

Class ThreadPoolSupplier.Builder

java.lang.Object

io.helidon.common.configurable.ThreadPoolSupplier.Builder

All Implemented Interfaces:

Builder<ThreadPoolSupplier>, Supplier<ThreadPoolSupplier>

Enclosing class:

ThreadPoolSupplier

public static final class ThreadPoolSupplier.Builder
extends Object
implements Builder<ThreadPoolSupplier>

A fluent API builder for ThreadPoolSupplier.

Method Summary

Modifier and Type	Method	Description
ThreadPoolSupplier	build()	Build the instance from this builder.
ThreadPoolSupplier.Builder	config(Config config)	Load all properties for this thread pool from configuration.
ThreadPoolSupplier.Builder	corePoolSize(int corePoolSize)	Core pool size of the thread pool executor.
ThreadPoolSupplier.Builder	daemon(boolean daemon)	Is daemon of the thread pool executor.
ThreadPoolSupplier.Builder	keepAliveMinutes(int keepAliveMinutes)	Keep alive minutes of the thread pool executor.
ThreadPoolSupplier.Builder	maxPoolSize(int maxPoolSize)	Max pool size of the thread pool executor.
ThreadPoolSupplier.Builder	name(String name)	Name of this thread pool executor.
ThreadPoolSupplier.Builder	prestart(boolean prestart)	Whether to prestart core threads in this thread pool executor.
ThreadPoolSupplier.Builder	queueCapacity(int queueCapacity)	Queue capacity of the thread pool executor.
ThreadPoolSupplier.Builder	rejectionHandler(ThreadPool.RejectionHandler rejectionHandler)	Rejection policy of the thread pool executor.
ThreadPoolSupplier.Builder	threadNamePrefix(String threadNamePrefix)	Name prefix for threads in this thread pool executor.
ThreadPoolSupplier.Builder	virtualEnforced(boolean enforceVirtualThreads)	When configured to true, virtual thread executor service must be available, otherwise the built executor would fail to start.
ThreadPoolSupplier.Builder	virtualIfAvailable(boolean useVirtualThreads)	When configured to true, an unbounded virtual executor service (project Loom) will be used if available.

Methods inherited from class java.lang.Object

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

Methods inherited from interface io.helidon.common.Builder

get

Method Detail

build

public ThreadPoolSupplier build()

Description copied from interface: Builder

Build the instance from this builder.

Specified by:

build in interface Builder<ThreadPoolSupplier>

Returns:

instance of the built type

corePoolSize

public ThreadPoolSupplier.Builder corePoolSize(int corePoolSize)

Core pool size of the thread pool executor.

Parameters:

corePoolSize - see ThreadPoolExecutor.getCorePoolSize()

Returns:

updated builder instance

maxPoolSize

public ThreadPoolSupplier.Builder maxPoolSize(int maxPoolSize)

Max pool size of the thread pool executor.

Parameters:

maxPoolSize - see ThreadPoolExecutor.getMaximumPoolSize()

Returns:

updated builder instance

keepAliveMinutes

public ThreadPoolSupplier.Builder keepAliveMinutes(int keepAliveMinutes)

Keep alive minutes of the thread pool executor.

Parameters:

keepAliveMinutes - see ThreadPoolExecutor.getKeepAliveTime(TimeUnit)

Returns:

updated builder instance

queueCapacity

public ThreadPoolSupplier.Builder queueCapacity(int queueCapacity)

Queue capacity of the thread pool executor.

Parameters:

queueCapacity - capacity of the queue backing the executor

Returns:

updated builder instance

daemon

public ThreadPoolSupplier.Builder daemon(boolean daemon)

Is daemon of the thread pool executor.

Parameters:

daemon - whether the threads are daemon threads

Returns:

updated builder instance

name

public ThreadPoolSupplier.Builder name(String name)

Name of this thread pool executor.

Parameters:

name - the pool name

Returns:

updated builder instance

rejectionHandler

public ThreadPoolSupplier.Builder rejectionHandler(ThreadPool.RejectionHandler rejectionHandler)

Rejection policy of the thread pool executor.

Parameters:

rejectionHandler - the rejection policy

Returns:

updated builder instance

threadNamePrefix

public ThreadPoolSupplier.Builder threadNamePrefix(String threadNamePrefix)

Name prefix for threads in this thread pool executor.

Parameters:

threadNamePrefix - prefix of a thread name

Returns:

updated builder instance

prestart

public ThreadPoolSupplier.Builder prestart(boolean prestart)

Whether to prestart core threads in this thread pool executor.

Parameters:

prestart - whether to prestart the threads

Returns:

updated builder instance

config

public ThreadPoolSupplier.Builder config(Config config)

Load all properties for this thread pool from configuration.

Optional Configuration Parameters

key	default value	description
core-pool-size	10	The number of threads to keep in the pool.
max-pool-size	50	The maximum number of threads to allow in the pool.
keep-alive-minutes	3	When the number of threads is greater than the core, this is the maximum time that excess idle threads will wait for new tasks before terminating.
queue-capacity	10000	The maximum number of tasks that the queue can contain before new tasks are rejected.
is-daemon	true	Whether or not all threads in the pool should be set as daemon.
thread-name-prefix	"helidon-"	The prefix used to generate names for new threads.
should-prestart	true	Whether or not all core threads should be started when the pool is created.

Experimental Configuration Parameters (subject to change)

key	default value	description
growth-threshold	256	The queue size above which pool growth will be considered if the pool is not fixed size.
growth-rate	5	The percentage of task submissions that should result in adding a thread, expressed as a value from 0 to 100. For non-zero values the rate is applied when all of the following are true: the pool size is below the maximum, and there are no idle threads, and the number of tasks in the queue exceeds the growthThreshold For example, a rate of 20 means that while these conditions are met one thread will be added for every 5 submitted tasks. A rate of 0 selects the default ThreadPoolExecutor growth behavior: a thread is added only when a submitted task is rejected because the queue is full.

Parameters:

config - config located on the key of executor-service

Returns:

updated builder instance

virtualEnforced

public ThreadPoolSupplier.Builder virtualEnforced(boolean enforceVirtualThreads)

When configured to true, virtual thread executor service must be available, otherwise the built executor would fail to start.

Parameters:

enforceVirtualThreads - whether to enforce virtual threads, defaults to false

Returns:

updated builder instance

See Also:

virtualIfAvailable(boolean)

virtualIfAvailable

public ThreadPoolSupplier.Builder virtualIfAvailable(boolean useVirtualThreads)

When configured to true, an unbounded virtual executor service (project Loom) will be used if available. This is an experimental feature.

If enabled and available, all other configuration options of this executor service are ignored!

Parameters:

useVirtualThreads - whether to use virtual threads or not, defaults to false

Returns:

updated builder instance