content: /**
   * Licensed to the Apache Software Foundation (ASF) under one
   * or more contributor license agreements.  See the NOTICE file
   * distributed with this work for additional information
   * regarding copyright ownership.  The ASF licenses this file
   * to you 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.jstorm.common.metric;
  
  import com.google.common.base.Joiner;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  import backtype.storm.utils.DisruptorQueue;
  
  import com.codahale.metrics.Gauge;
  import com.codahale.metrics.health.HealthCheck;
  
  public class QueueGauge extends HealthCheck implements Gauge<Double> {
      private static final Logger LOG = LoggerFactory.getLogger(QueueGauge.class);
  
      public static final String QUEUE_IS_FULL = " is full";
  
      DisruptorQueue queue;
      String name;
      Result healthy;
  
      public QueueGauge(DisruptorQueue queue, String... names) {
          this.queue = queue;
          this.name = Joiner.on("-").join(names);
          this.healthy = HealthCheck.Result.healthy();
      }
  
      @Override
      public Double getValue() {
          return (double) queue.pctFull();
      }
  
      @Override
      protected Result check() throws Exception {
          Double ret = (double) queue.pctFull();
          if (ret > 0.9) {
              return HealthCheck.Result.unhealthy(name + QUEUE_IS_FULL);
          } else {
              return healthy;
          }
      }
  
  }
  