content: /*
   * Copyright (c) 2014, 2016, Oracle and/or its affiliates. All rights reserved.
   * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   *
   * This code is free software; you can redistribute it and/or modify it
   * under the terms of the GNU General Public License version 2 only, as
   * published by the Free Software Foundation.  Oracle designates this
   * particular file as subject to the "Classpath" exception as provided
   * by Oracle in the LICENSE file that accompanied this code.
   *
   * This code is distributed in the hope that it will be useful, but WITHOUT
   * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
   * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
   * version 2 for more details (a copy is included in the LICENSE file that
   * accompanied this code).
   *
   * You should have received a copy of the GNU General Public License version
   * 2 along with this work; if not, write to the Free Software Foundation,
   * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
   *
   * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
   * or visit www.oracle.com if you need additional information or have any
   * questions.
   */
  
  package openjdk.tools.sjavac.comp;
  
  import openjdk.tools.javac.main.Main.Result;
  import openjdk.tools.sjavac.Log;
  import openjdk.tools.sjavac.server.Sjavac;
  
  import java.util.Objects;
  import java.util.concurrent.ExecutorService;
  import java.util.concurrent.Executors;
  import java.util.concurrent.TimeUnit;
  
  /**
   * An sjavac implementation that limits the number of concurrent calls by
   * wrapping invocations in Callables and delegating them to a FixedThreadPool.
   *
   *  <p><b>This is NOT part of any supported API.
   *  If you write code that depends on this, you do so at your own risk.
   *  This code and its internal interfaces are subject to change or
   *  deletion without notice.</b>
   */
  public class PooledSjavac implements Sjavac {
  
      final Sjavac delegate;
      final ExecutorService pool;
  
      public PooledSjavac(Sjavac delegate, int poolsize) {
          Objects.requireNonNull(delegate);
          this.delegate = delegate;
          pool = Executors.newFixedThreadPool(poolsize);
      }
  
      @Override
      public Result compile(String[] args) {
          Log log = Log.get();
          try {
              return pool.submit(() -> {
                  Log.setLogForCurrentThread(log);
                  return delegate.compile(args);
              }).get();
          } catch (Exception e) {
              e.printStackTrace();
              throw new RuntimeException("Error during compile", e);
          }
      }
  
      @Override
      public void shutdown() {
          Log.debug("Shutting down PooledSjavac");
          pool.shutdown(); // Disable new tasks from being submitted
          try {
              // Wait a while for existing tasks to terminate
              if (!pool.awaitTermination(60, TimeUnit.SECONDS)) {
                  pool.shutdownNow(); // Cancel currently executing tasks
                  // Wait a while for tasks to respond to being cancelled
                  if (!pool.awaitTermination(60, TimeUnit.SECONDS))
                      Log.error("ThreadPool did not terminate");
              }
          } catch (InterruptedException ie) {
            // (Re-)Cancel if current thread also interrupted
            pool.shutdownNow();
            // Preserve interrupt status
            Thread.currentThread().interrupt();
          }
  
          delegate.shutdown();
      }
  
  }
  