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.plugin;
  
  import com.codahale.metrics.Timer;
  
  import java.util.concurrent.TimeUnit;
  
  // collect metrics per gremlin query
  public interface MetricsCollector {
      long getStartMillis();
  
      long getElapsedMillis();
  
      void stop();
  
      class Gremlin implements MetricsCollector {
          private final Timer.Context timeContext;
          private final long startMillis;
          private long elapsedMillis;
  
          public Gremlin(Timer timer) {
              this.timeContext = timer.time();
              this.startMillis = System.currentTimeMillis();
          }
  
          @Override
          public long getStartMillis() {
              return this.startMillis;
          }
  
          @Override
          public long getElapsedMillis() {
              return this.elapsedMillis;
          }
  
          @Override
          public void stop() {
              this.elapsedMillis = TimeUnit.NANOSECONDS.toMillis(timeContext.stop());
          }
      }
  
      class Cypher implements MetricsCollector {
          private final long startMills;
          private long endMills;
  
          public Cypher(long startMills) {
              this.startMills = startMills;
          }
  
          @Override
          public void stop() {
              this.endMills = System.currentTimeMillis();
          }
  
          @Override
          public long getStartMillis() {
              return this.startMills;
          }
  
          @Override
          public long getElapsedMillis() {
              return this.endMills - this.startMills;
          }
      }
  }
  