content: /*
   * Copyright 1999-2018 Alibaba Group Holding Ltd.
   *
   * 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 com.alibaba.nacos.common.utils;
  
  import org.slf4j.Logger;
  
  import java.util.Objects;
  import java.util.concurrent.CountDownLatch;
  import java.util.concurrent.ExecutorService;
  import java.util.concurrent.TimeUnit;
  
  /**
   * Thread utils.
   *
   * @author <a href="mailto:liaochuntao@live.com">liaochuntao</a>
   */
  public final class ThreadUtils {
      
      private ThreadUtils() {
      }
      
      private static final int THREAD_MULTIPLER = 2;
      
      /**
       * Sleep.
       *
       * @param millis sleep millisecond
       */
      public static void sleep(long millis) {
          try {
              Thread.sleep(millis);
          } catch (InterruptedException e) {
              Thread.currentThread().interrupt();
          }
      }
      
      public static void countDown(CountDownLatch latch) {
          Objects.requireNonNull(latch, "latch");
          latch.countDown();
      }
      
      /**
       * Await count down latch.
       *
       * @param latch count down latch
       */
      public static void latchAwait(CountDownLatch latch) {
          try {
              latch.await();
          } catch (InterruptedException e) {
              Thread.currentThread().interrupt();
          }
      }
      
      /**
       * Await count down latch with timeout.
       *
       * @param latch count down latch
       * @param time  timeout time
       * @param unit  time unit
       */
      public static void latchAwait(CountDownLatch latch, long time, TimeUnit unit) {
          try {
              latch.await(time, unit);
          } catch (InterruptedException e) {
              Thread.currentThread().interrupt();
          }
      }
      
      /**
       * Through the number of cores, calculate the appropriate number of threads; 1.5-2 times the number of CPU cores.
       *
       * @return thread count
       */
      public static int getSuitableThreadCount() {
          return getSuitableThreadCount(THREAD_MULTIPLER);
      }
      
      /**
       * Through the number of cores, calculate the appropriate number of threads.
       *
       * @param threadMultiple multiple time of cores
       * @return thread count
       */
      public static int getSuitableThreadCount(int threadMultiple) {
          final int coreCount = PropertyUtils.getProcessorsCount();
          int workerCount = 1;
          while (workerCount < coreCount * threadMultiple) {
              workerCount <<= 1;
          }
          return workerCount;
      }
      
      public static void shutdownThreadPool(ExecutorService executor) {
          shutdownThreadPool(executor, null);
      }
      
      /**
       * Shutdown thread pool.
       *
       * @param executor thread pool
       * @param logger   logger
       */
      public static void shutdownThreadPool(ExecutorService executor, Logger logger) {
          executor.shutdown();
          int retry = 3;
          while (retry > 0) {
              retry--;
              try {
                  if (executor.awaitTermination(100, TimeUnit.MILLISECONDS)) {
                      return;
                  }
              } catch (InterruptedException e) {
                  executor.shutdownNow();
                  Thread.interrupted();
              } catch (Throwable ex) {
                  if (logger != null) {
                      logger.error("ThreadPoolManager shutdown executor has error : ", ex);
                  }
              }
          }
          executor.shutdownNow();
      }
      
      public static void addShutdownHook(Runnable runnable) {
          Runtime.getRuntime().addShutdownHook(new Thread(runnable));
      }
      
  }
  