com.avaje.ebeaninternal.server.lib.DaemonThreadPool Maven / Gradle / Ivy
package com.avaje.ebeaninternal.server.lib;
import java.util.concurrent.LinkedBlockingQueue;
import java.util.concurrent.ThreadPoolExecutor;
import java.util.concurrent.TimeUnit;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* The Thread Pool based on Daemon threads.
*
* @author rbygrave
*/
public final class DaemonThreadPool extends ThreadPoolExecutor {
private static final Logger logger = LoggerFactory.getLogger(DaemonThreadPool.class);
private final String namePrefix;
private final int shutdownWaitSeconds;
/**
* Construct the DaemonThreadPool.
*
* @param coreSize
* the core size of the thread pool.
* @param keepAliveSecs
* the time in seconds idle threads are keep alive
* @param shutdownWaitSeconds
* the time in seconds allowed for the pool to shutdown nicely. After
* this the pool is forced to shutdown.
*/
public DaemonThreadPool(int coreSize, int maximumPoolSize, long keepAliveSecs, int shutdownWaitSeconds, String namePrefix) {
super(coreSize, maximumPoolSize, keepAliveSecs, TimeUnit.SECONDS, new LinkedBlockingQueue(), new DaemonThreadFactory(namePrefix));
allowCoreThreadTimeOut(true);
this.shutdownWaitSeconds = shutdownWaitSeconds;
this.namePrefix = namePrefix;
}
/**
* Register a shutdown hook with the JVM Runtime.
*/
public void registerShutdownHook() {
Runtime.getRuntime().addShutdownHook(new ShutdownHook());
}
/**
* Shutdown this thread pool nicely if possible.
*
* This will wait a maximum of 20 seconds before terminating any threads still
* working.
*
*/
public void shutdown() {
synchronized (this) {
if (super.isShutdown()) {
logger.debug("DaemonThreadPool[" + namePrefix + "] already shut down");
return;
}
try {
logger.debug("DaemonThreadPool[" + namePrefix + "] shutting down...");
super.shutdown();
if (!super.awaitTermination(shutdownWaitSeconds, TimeUnit.SECONDS)) {
logger.info("DaemonThreadPool[" + namePrefix+ "] shut down timeout exceeded. Terminating running threads.");
super.shutdownNow();
}
} catch (Exception e) {
logger.error("Error during shutdown of DaemonThreadPool[" + namePrefix + "]", e);
e.printStackTrace();
}
}
}
/**
* Fired by the JVM Runtime shutdown.
*/
private class ShutdownHook extends Thread {
@Override
public void run() {
shutdown();
}
}
}