org.springframework.boot.task.TaskExecutorBuilder Maven / Gradle / Ivy
/*
* Copyright 2012-2018 the original author or authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* https://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.springframework.boot.task;
import java.time.Duration;
import java.util.Arrays;
import java.util.Collections;
import java.util.LinkedHashSet;
import java.util.Set;
import org.springframework.beans.BeanUtils;
import org.springframework.boot.context.properties.PropertyMapper;
import org.springframework.core.task.TaskDecorator;
import org.springframework.core.task.TaskExecutor;
import org.springframework.scheduling.concurrent.ThreadPoolTaskExecutor;
import org.springframework.util.Assert;
import org.springframework.util.CollectionUtils;
/**
* Builder that can be used to configure and create a {@link TaskExecutor}. Provides
* convenience methods to set common {@link ThreadPoolTaskExecutor} settings and register
* {@link #taskDecorator(TaskDecorator)}). For advanced configuration, consider using
* {@link TaskExecutorCustomizer}.
*
* In a typical auto-configured Spring Boot application this builder is available as a
* bean and can be injected whenever a {@link TaskExecutor} is needed.
*
* @author Stephane Nicoll
* @since 2.1.0
*/
public class TaskExecutorBuilder {
private final Integer queueCapacity;
private final Integer corePoolSize;
private final Integer maxPoolSize;
private final Boolean allowCoreThreadTimeOut;
private final Duration keepAlive;
private final String threadNamePrefix;
private final TaskDecorator taskDecorator;
private final Set customizers;
public TaskExecutorBuilder() {
this.queueCapacity = null;
this.corePoolSize = null;
this.maxPoolSize = null;
this.allowCoreThreadTimeOut = null;
this.keepAlive = null;
this.threadNamePrefix = null;
this.taskDecorator = null;
this.customizers = null;
}
private TaskExecutorBuilder(Integer queueCapacity, Integer corePoolSize,
Integer maxPoolSize, Boolean allowCoreThreadTimeOut, Duration keepAlive,
String threadNamePrefix, TaskDecorator taskDecorator,
Set customizers) {
this.queueCapacity = queueCapacity;
this.corePoolSize = corePoolSize;
this.maxPoolSize = maxPoolSize;
this.allowCoreThreadTimeOut = allowCoreThreadTimeOut;
this.keepAlive = keepAlive;
this.threadNamePrefix = threadNamePrefix;
this.taskDecorator = taskDecorator;
this.customizers = customizers;
}
/**
* Set the capacity of the queue. An unbounded capacity does not increase the pool and
* therefore ignores {@link #maxPoolSize(int) maxPoolSize}.
* @param queueCapacity the queue capacity to set
* @return a new builder instance
*/
public TaskExecutorBuilder queueCapacity(int queueCapacity) {
return new TaskExecutorBuilder(queueCapacity, this.corePoolSize, this.maxPoolSize,
this.allowCoreThreadTimeOut, this.keepAlive, this.threadNamePrefix,
this.taskDecorator, this.customizers);
}
/**
* Set the core number of threads. Effectively that maximum number of threads as long
* as the queue is not full.
*
* Core threads can grow and shrink if {@link #allowCoreThreadTimeOut(boolean)} is
* enabled.
* @param corePoolSize the core pool size to set
* @return a new builder instance
*/
public TaskExecutorBuilder corePoolSize(int corePoolSize) {
return new TaskExecutorBuilder(this.queueCapacity, corePoolSize, this.maxPoolSize,
this.allowCoreThreadTimeOut, this.keepAlive, this.threadNamePrefix,
this.taskDecorator, this.customizers);
}
/**
* Set the maximum allowed number of threads. When the {@link #queueCapacity(int)
* queue} is full, the pool can expand up to that size to accommodate the load.
*
* If the {@link #queueCapacity(int) queue capacity} is unbounded, this setting is
* ignored.
* @param maxPoolSize the max pool size to set
* @return a new builder instance
*/
public TaskExecutorBuilder maxPoolSize(int maxPoolSize) {
return new TaskExecutorBuilder(this.queueCapacity, this.corePoolSize, maxPoolSize,
this.allowCoreThreadTimeOut, this.keepAlive, this.threadNamePrefix,
this.taskDecorator, this.customizers);
}
/**
* Set whether core threads are allow to time out. When enabled, this enables dynamic
* growing and shrinking of the pool.
* @param allowCoreThreadTimeOut if core threads are allowed to time out
* @return a new builder instance
*/
public TaskExecutorBuilder allowCoreThreadTimeOut(boolean allowCoreThreadTimeOut) {
return new TaskExecutorBuilder(this.queueCapacity, this.corePoolSize,
this.maxPoolSize, allowCoreThreadTimeOut, this.keepAlive,
this.threadNamePrefix, this.taskDecorator, this.customizers);
}
/**
* Set the time limit for which threads may remain idle before being terminated.
* @param keepAlive the keep alive to set
* @return a new builder instance
*/
public TaskExecutorBuilder keepAlive(Duration keepAlive) {
return new TaskExecutorBuilder(this.queueCapacity, this.corePoolSize,
this.maxPoolSize, this.allowCoreThreadTimeOut, keepAlive,
this.threadNamePrefix, this.taskDecorator, this.customizers);
}
/**
* Set the prefix to use for the names of newly created threads.
* @param threadNamePrefix the thread name prefix to set
* @return a new builder instance
*/
public TaskExecutorBuilder threadNamePrefix(String threadNamePrefix) {
return new TaskExecutorBuilder(this.queueCapacity, this.corePoolSize,
this.maxPoolSize, this.allowCoreThreadTimeOut, this.keepAlive,
threadNamePrefix, this.taskDecorator, this.customizers);
}
/**
* Set the {@link TaskDecorator} to use or {@code null} to not use any.
* @param taskDecorator the task decorator to use
* @return a new builder instance
*/
public TaskExecutorBuilder taskDecorator(TaskDecorator taskDecorator) {
return new TaskExecutorBuilder(this.queueCapacity, this.corePoolSize,
this.maxPoolSize, this.allowCoreThreadTimeOut, this.keepAlive,
this.threadNamePrefix, taskDecorator, this.customizers);
}
/**
* Set the {@link TaskExecutorCustomizer TaskExecutorCustomizers} that should be
* applied to the {@link ThreadPoolTaskExecutor}. Customizers are applied in the order
* that they were added after builder configuration has been applied. Setting this
* value will replace any previously configured customizers.
* @param customizers the customizers to set
* @return a new builder instance
* @see #additionalCustomizers(TaskExecutorCustomizer...)
*/
public TaskExecutorBuilder customizers(TaskExecutorCustomizer... customizers) {
Assert.notNull(customizers, "Customizers must not be null");
return customizers(Arrays.asList(customizers));
}
/**
* Set the {@link TaskExecutorCustomizer TaskExecutorCustomizers} that should be
* applied to the {@link ThreadPoolTaskExecutor}. Customizers are applied in the order
* that they were added after builder configuration has been applied. Setting this
* value will replace any previously configured customizers.
* @param customizers the customizers to set
* @return a new builder instance
* @see #additionalCustomizers(TaskExecutorCustomizer...)
*/
public TaskExecutorBuilder customizers(Iterable customizers) {
Assert.notNull(customizers, "Customizers must not be null");
return new TaskExecutorBuilder(this.queueCapacity, this.corePoolSize,
this.maxPoolSize, this.allowCoreThreadTimeOut, this.keepAlive,
this.threadNamePrefix, this.taskDecorator, append(null, customizers));
}
/**
* Add {@link TaskExecutorCustomizer TaskExecutorCustomizers} that should be applied
* to the {@link ThreadPoolTaskExecutor}. Customizers are applied in the order that
* they were added after builder configuration has been applied.
* @param customizers the customizers to add
* @return a new builder instance
* @see #customizers(TaskExecutorCustomizer...)
*/
public TaskExecutorBuilder additionalCustomizers(
TaskExecutorCustomizer... customizers) {
Assert.notNull(customizers, "Customizers must not be null");
return additionalCustomizers(Arrays.asList(customizers));
}
/**
* Add {@link TaskExecutorCustomizer TaskExecutorCustomizers} that should be applied
* to the {@link ThreadPoolTaskExecutor}. Customizers are applied in the order that
* they were added after builder configuration has been applied.
* @param customizers the customizers to add
* @return a new builder instance
* @see #customizers(TaskExecutorCustomizer...)
*/
public TaskExecutorBuilder additionalCustomizers(
Iterable customizers) {
Assert.notNull(customizers, "Customizers must not be null");
return new TaskExecutorBuilder(this.queueCapacity, this.corePoolSize,
this.maxPoolSize, this.allowCoreThreadTimeOut, this.keepAlive,
this.threadNamePrefix, this.taskDecorator,
append(this.customizers, customizers));
}
/**
* Build a new {@link ThreadPoolTaskExecutor} instance and configure it using this
* builder.
* @return a configured {@link ThreadPoolTaskExecutor} instance.
* @see #build(Class)
* @see #configure(ThreadPoolTaskExecutor)
*/
public ThreadPoolTaskExecutor build() {
return build(ThreadPoolTaskExecutor.class);
}
/**
* Build a new {@link ThreadPoolTaskExecutor} instance of the specified type and
* configure it using this builder.
* @param the type of task executor
* @param taskExecutorClass the template type to create
* @return a configured {@link ThreadPoolTaskExecutor} instance.
* @see #build()
* @see #configure(ThreadPoolTaskExecutor)
*/
public T build(Class taskExecutorClass) {
return configure(BeanUtils.instantiateClass(taskExecutorClass));
}
/**
* Configure the provided {@link ThreadPoolTaskExecutor} instance using this builder.
* @param the type of task executor
* @param taskExecutor the {@link ThreadPoolTaskExecutor} to configure
* @return the task executor instance
* @see #build()
* @see #build(Class)
*/
public T configure(T taskExecutor) {
PropertyMapper map = PropertyMapper.get().alwaysApplyingWhenNonNull();
map.from(this.queueCapacity).to(taskExecutor::setQueueCapacity);
map.from(this.corePoolSize).to(taskExecutor::setCorePoolSize);
map.from(this.maxPoolSize).to(taskExecutor::setMaxPoolSize);
map.from(this.keepAlive).asInt(Duration::getSeconds)
.to(taskExecutor::setKeepAliveSeconds);
map.from(this.allowCoreThreadTimeOut).to(taskExecutor::setAllowCoreThreadTimeOut);
map.from(this.threadNamePrefix).whenHasText()
.to(taskExecutor::setThreadNamePrefix);
map.from(this.taskDecorator).to(taskExecutor::setTaskDecorator);
if (!CollectionUtils.isEmpty(this.customizers)) {
this.customizers.forEach((customizer) -> customizer.customize(taskExecutor));
}
return taskExecutor;
}
private Set append(Set set, Iterable additions) {
Set result = new LinkedHashSet<>((set != null) ? set : Collections.emptySet());
additions.forEach(result::add);
return Collections.unmodifiableSet(result);
}
}