com.google.tsunami.common.concurrent.ScheduledThreadPoolModule Maven / Gradle / Ivy
/*
* Copyright 2020 Google LLC
*
* 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
*
* http://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 com.google.tsunami.common.concurrent;
import static com.google.common.base.Preconditions.checkArgument;
import static java.util.concurrent.TimeUnit.SECONDS;
import com.google.common.util.concurrent.ListeningScheduledExecutorService;
import com.google.inject.Key;
import java.util.concurrent.RejectedExecutionHandler;
import java.util.concurrent.ScheduledExecutorService;
import java.util.concurrent.ScheduledThreadPoolExecutor;
import java.util.concurrent.ThreadFactory;
import javax.inject.Singleton;
/**
* A helper module for binding a scheduled thread pool. The module will bind a {@link
* ScheduledExecutorService} and a {@link ListeningScheduledExecutorService} to a singleton thread
* pool that is annotated with the annotation passed to the builder.
*/
public final class ScheduledThreadPoolModule
extends BaseThreadPoolModule {
ScheduledThreadPoolModule(Builder builder) {
super(builder);
}
@Override
void configureThreadPool(Key key) {
bind(key.ofType(ScheduledExecutorService.class)).to(key);
bind(key).toProvider(new ScheduledThreadPoolProvider()).in(Singleton.class);
}
private final class ScheduledThreadPoolProvider extends BaseThreadPoolProvider {
@Override
ScheduledThreadPoolExecutor createThreadPool(
int coreSize,
int maxSize,
long keepAliveSeconds,
ThreadFactory factory,
RejectedExecutionHandler rejectedExecutionHandler) {
ScheduledThreadPoolExecutor scheduledThreadPoolExecutor =
new ScheduledThreadPoolExecutor(coreSize, factory, rejectedExecutionHandler);
scheduledThreadPoolExecutor.setMaximumPoolSize(maxSize);
scheduledThreadPoolExecutor.setKeepAliveTime(keepAliveSeconds, SECONDS);
return scheduledThreadPoolExecutor;
}
}
/**
* Builder for {@link ScheduledThreadPoolModule}.
*
* NOTE: Unlike {@link ThreadPoolModule}, {@link ScheduledThreadPoolExecutor} acts as a
* fixed-sized pool using {@code corePoolSize} threads and an unbounded queue. So this builder
* only allows users to set a fixed thread pool size.
*/
public static final class Builder
extends BaseThreadPoolModuleBuilder {
public Builder() {
super(ListeningScheduledExecutorService.class);
}
@Override
Builder self() {
return this;
}
/**
* Sets the size of the thread pool.
*
* @param size the size of the thread pool.
* @return the {@link Builder} instance itself.
*/
public Builder setSize(int size) {
checkArgument(size > 0, "Thread pool size should be positive.");
setCoreSize(size);
setMaxSize(size);
return this;
}
@Override
void validate() {}
@Override
ScheduledThreadPoolModule newModule() {
return new ScheduledThreadPoolModule(this);
}
}
}