content: /*
   *
   *  * Copyright 2020 Alibaba Group Holding Limited.
   *  *
   *  * 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.graphscope.gremlin.metric;
  
  import com.alibaba.graphscope.common.metric.Metric;
  import com.alibaba.graphscope.gremlin.Utils;
  
  import org.apache.tinkerpop.gremlin.server.GremlinServer;
  
  import java.util.concurrent.ExecutorService;
  import java.util.concurrent.ThreadPoolExecutor;
  
  public class GremlinExecutorQueueMetric implements Metric<Integer> {
      private final ExecutorService executorService;
  
      public GremlinExecutorQueueMetric(GremlinServer server) {
          this.executorService =
                  Utils.getFieldValue(GremlinServer.class, server, "gremlinExecutorService");
      }
  
      @Override
      public Key getKey() {
          return KeyFactory.GREMLIN_EXECUTOR_QUEUE;
      }
  
      @Override
      public Integer getValue() {
          return (executorService instanceof ThreadPoolExecutor)
                  ? ((ThreadPoolExecutor) executorService).getQueue().size()
                  : ValueFactory.INVALID_INT;
      }
  }
  