net.e6tech.elements.common.util.concurrent.LazyThreadPool Maven / Gradle / Ivy
/*
* Copyright 2015-2022 Futeh Kao
*
* 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 net.e6tech.elements.common.util.concurrent;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.ThreadFactory;
import java.util.function.Function;
public class LazyThreadPool extends ThreadPool {
private Function executorServiceFunction;
public LazyThreadPool(String name, Function newPool) {
super(name, (ExecutorService) null);
this.executorServiceFunction = newPool;
}
protected synchronized ExecutorService executorService() {
if (executorService == null) { // double sync lock. Won't work during heavy multithreaded load. However, for start up, it works fine.
synchronized (this) {
if (executorService == null) {
executorService = executorServiceFunction.apply(this);
}
}
}
return executorService;
}
}