/*

  * 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.yammer.metrics.core;

 import com.yammer.metrics.stats.Snapshot;

 /**

  * An empty Metrics' Histogram that does nothing.

  */

 public class NoOpHistogram extends Histogram {

   /** singleton instance for everyone to use */

   public static final NoOpHistogram INSTANCE = new NoOpHistogram();

   /** do not instantiate */

   private NoOpHistogram() { super(SampleType.UNIFORM); }

   @Override

   public void clear() { }

   @Override

   public void update(int value) { }

   @Override

   public void update(long value) { }

   @Override

   public long count() { return 0; }

   @Override

   public double max() { return 0.0; }

   @Override

   public double min() { return 0.0; }

   @Override

   public double mean() { return 0.0; }

   @Override

   public double stdDev() { return 0.0; }

   @Override

   public double sum() { return 0.0; }

   @Override

   public Snapshot getSnapshot() { return new Snapshot(new double[0]); }

   @Override

   public <T> void processWith(MetricProcessor<T> processor, MetricName name,

                               T context)

     throws Exception { }

 }