| // Copyright (c) 2018 The Jaeger Authors |
| // |
| // 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 metrics |
| |
| // Histogram that keeps track of a distribution of values. |
| type Histogram interface { |
| // Records the value passed in. |
| Record(float64) |
| } |
| |
| // NullHistogram that does nothing |
| var NullHistogram Histogram = nullHistogram{} |
| |
| type nullHistogram struct{} |
| |
| func (nullHistogram) Record(float64) {} |