forklift.concurrent.Executors Maven / Gradle / Ivy
package forklift.concurrent;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.SynchronousQueue;
import java.util.concurrent.ThreadFactory;
import java.util.concurrent.ThreadPoolExecutor;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.atomic.AtomicInteger;
/**
* Forklift core thread pool.
* @author zdavep
*/
public final class Executors {
// Base value for determining thread pool size.
private static final int cpus = Runtime.getRuntime().availableProcessors();
/**
* Disable instance creation.
*/
private Executors() {}
/**
* Allows us to create daemon threads with meaningful names.
*/
private static ThreadFactory daemonThreadFactory(final String name) {
return new ThreadFactory() {
private final AtomicInteger counter = new AtomicInteger();
@Override public Thread newThread(Runnable r) {
final Thread thread = new Thread(r);
thread.setName(name + "-" + counter.incrementAndGet());
thread.setDaemon(true);
return thread;
}
};
}
/**
* A core thread pool factory method that returns a "better" alternative to a cached thread pool.
*/
public static ExecutorService newCoreThreadPool(final String name) {
final ThreadPoolExecutor pool = new ThreadPoolExecutor(
(2 * cpus), (6 * cpus), 60, TimeUnit.SECONDS, new SynchronousQueue(), daemonThreadFactory(name)
);
pool.setRejectedExecutionHandler(new ThreadPoolExecutor.CallerRunsPolicy());
return pool;
}
}