SCM-Manager/scm-webapp/src/main/java/sonia/scm/search/IndexQueue.java

/*
 * MIT License
 *
 * Copyright (c) 2020-present Cloudogu GmbH and Contributors
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */

package sonia.scm.search;

import com.google.common.annotations.VisibleForTesting;

import javax.inject.Inject;
import javax.inject.Singleton;
import java.io.Closeable;
import java.io.IOException;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.atomic.AtomicLong;

@Singleton
public class IndexQueue implements Closeable {

  private final ExecutorService executor = Executors.newSingleThreadExecutor();

  private final AtomicLong size = new AtomicLong(0);

  private final LuceneIndexFactory indexFactory;

  @Inject
  public IndexQueue(LuceneIndexFactory indexFactory) {
    this.indexFactory = indexFactory;
  }

  public <T> Index<T> getQueuedIndex(IndexParams indexParams) {
    return new QueuedIndex<>(this, indexParams);
  }

  public LuceneIndexFactory getIndexFactory() {
    return indexFactory;
  }

  <T> void enqueue(IndexQueueTaskWrapper<T> task) {
    size.incrementAndGet();
    executor.execute(() -> {
      task.run();
      size.decrementAndGet();
    });
  }

  @VisibleForTesting
  long getSize() {
    return size.get();
  }

  @Override
  public void close() throws IOException {
    executor.shutdown();
  }
}