/**
    * 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.hadoop.hbase;
  
  import java.util.concurrent.ThreadFactory;
  import java.util.concurrent.atomic.AtomicInteger;
  
  /**
   * Thread factory that creates daemon threads
   */
  public class DaemonThreadFactory implements ThreadFactory {
    static final AtomicInteger poolNumber = new AtomicInteger(1);
    final ThreadGroup group;
    final AtomicInteger threadNumber = new AtomicInteger(1);
    final String namePrefix;
  
    public DaemonThreadFactory(String name) {
      SecurityManager s = System.getSecurityManager();
      group = (s != null) ? s.getThreadGroup() : Thread.currentThread().getThreadGroup();
      namePrefix = name + poolNumber.getAndIncrement() + "-thread-";
    }
  
    @Override
    public Thread newThread(Runnable r) {
      Thread t = new Thread(group, r, namePrefix + threadNumber.getAndIncrement(), 0);
      if (!t.isDaemon()) {
        t.setDaemon(true);
      }
      if (t.getPriority() != Thread.NORM_PRIORITY) {
        t.setPriority(Thread.NORM_PRIORITY);
      }
      return t;
    }
  }