| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you 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 org.apache.felix.configurator.impl; |
| |
| import java.util.ArrayList; |
| import java.util.List; |
| import java.util.concurrent.Executors; |
| import java.util.concurrent.ThreadFactory; |
| |
| import org.apache.felix.configurator.impl.logger.SystemLogger; |
| |
| public class WorkerQueue implements Runnable { |
| |
| private final ThreadFactory threadFactory; |
| |
| private final List<Runnable> tasks = new ArrayList<>(); |
| |
| private volatile Thread backgroundThread; |
| |
| private volatile boolean stopped = false; |
| |
| public WorkerQueue() { |
| this.threadFactory = Executors.defaultThreadFactory(); |
| } |
| |
| public void stop() { |
| synchronized ( this.tasks ) { |
| this.stopped = true; |
| } |
| } |
| |
| public void enqueue(final Runnable r) { |
| synchronized ( this.tasks ) { |
| if ( !this.stopped ) { |
| this.tasks.add(r); |
| if ( this.backgroundThread == null ) { |
| this.backgroundThread = this.threadFactory.newThread(this); |
| this.backgroundThread.setDaemon(true); |
| this.backgroundThread.setName("Apache Felix Configurator Worker Thread"); |
| this.backgroundThread.start(); |
| } |
| } |
| } |
| } |
| |
| @Override |
| public void run() { |
| Runnable r; |
| do { |
| r = null; |
| synchronized ( this.tasks ) { |
| if ( !this.stopped && !this.tasks.isEmpty() ) { |
| r = this.tasks.remove(0); |
| } else { |
| this.backgroundThread = null; |
| } |
| } |
| if ( r != null ) { |
| try { |
| r.run(); |
| } catch ( final Throwable t) { |
| // just to be sure our loop never dies |
| SystemLogger.error("Error processing task" + t.getMessage(), t); |
| } |
| } |
| } while ( r != null ); |
| } |
| } |