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 org.apache.cassandra.metrics;
  
  import com.codahale.metrics.Counter;
  import com.codahale.metrics.Gauge;
  import com.codahale.metrics.RatioGauge;
  import org.apache.cassandra.cql3.QueryProcessor;
  
  import static org.apache.cassandra.metrics.CassandraMetricsRegistry.Metrics;
  
  public class CQLMetrics
  {
      public static final String TYPE_NAME = "CQL";
      private static final MetricNameFactory factory = new DefaultNameFactory(TYPE_NAME);
  
      public final Counter regularStatementsExecuted;
      public final Counter preparedStatementsExecuted;
      public final Counter preparedStatementsEvicted;
  
      public final Counter useStatementsExecuted;
  
      public final Gauge<Integer> preparedStatementsCount;
      public final Gauge<Double> preparedStatementsRatio;
      public final Gauge<Long> preparedStatementsCacheSize;
  
      public CQLMetrics()
      {
          regularStatementsExecuted = Metrics.counter(factory.createMetricName("RegularStatementsExecuted"));
          preparedStatementsExecuted = Metrics.counter(factory.createMetricName("PreparedStatementsExecuted"));
          preparedStatementsEvicted = Metrics.counter(factory.createMetricName("PreparedStatementsEvicted"));
  
          useStatementsExecuted = Metrics.counter(factory.createMetricName("UseStatementsExecuted"));
  
          preparedStatementsCount = Metrics.register(factory.createMetricName("PreparedStatementsCount"), QueryProcessor::preparedStatementsCount);
          preparedStatementsRatio = Metrics.register(factory.createMetricName("PreparedStatementsRatio"), new RatioGauge()
          {
              public Ratio getRatio()
              {
                  return Ratio.of(getNumerator(), getDenominator());
              }
  
              public double getNumerator()
              {
                  return preparedStatementsExecuted.getCount();
              }
  
              public double getDenominator()
              {
                  return regularStatementsExecuted.getCount() + preparedStatementsExecuted.getCount();
              }
          });
          preparedStatementsCacheSize = Metrics.register(factory.createMetricName("PreparedStatementsCacheSize"), QueryProcessor::preparedStatementsCacheMemoryUsedBytes);
      }
  }
  