| /* |
| * Copyright (C) 2018 The Android Open Source Project |
| * |
| * 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. |
| */ |
| #ifndef ANDROID_COUNTER_METRIC_H_ |
| #define ANDROID_COUNTER_METRIC_H_ |
| |
| #include <functional> |
| #include <map> |
| #include <string> |
| |
| #include <media/MediaAnalyticsItem.h> |
| #include <utils/Log.h> |
| |
| namespace android { |
| |
| |
| // The CounterMetric class is used to hold counts of operations or events. |
| // A CounterMetric can break down counts by a dimension specified by the |
| // application. E.g. an application may want to track counts broken out by |
| // error code or the size of some parameter. |
| // |
| // Example: |
| // |
| // CounterMetric<status_t> workCounter; |
| // workCounter("workCounterName", "result_status"); |
| // |
| // status_t err = DoWork(); |
| // |
| // // Increments the number of times called with the given error code. |
| // workCounter.Increment(err); |
| // |
| // std::map<int, int64_t> values; |
| // metric.ExportValues( |
| // [&] (int attribute_value, int64_t value) { |
| // values[attribute_value] = value; |
| // }); |
| // |
| // // Do something with the exported stat. |
| // |
| template<typename AttributeType> |
| class CounterMetric { |
| public: |
| // Instantiate the counter with the given metric name and |
| // attribute names. |attribute_names| must not be null. |
| CounterMetric( |
| const std::string& metric_name, |
| const std::string& attribute_name) |
| : metric_name_(metric_name), |
| attribute_name_(attribute_name) {} |
| |
| // Increment the count of times the operation occurred with this |
| // combination of attributes. |
| void Increment(AttributeType attribute) { |
| if (values_.find(attribute) == values_.end()) { |
| values_[attribute] = 1; |
| } else { |
| values_[attribute] = values_[attribute] + 1; |
| } |
| }; |
| |
| // Export the metrics to the provided |function|. Each value for Attribute |
| // has a separate count. As such, |function| will be called once per value |
| // of Attribute. |
| void ExportValues( |
| std::function<void (const AttributeType&, |
| const int64_t count)> function) const { |
| for (auto it = values_.begin(); it != values_.end(); it++) { |
| function(it->first, it->second); |
| } |
| } |
| |
| const std::string& metric_name() const { return metric_name_; }; |
| |
| private: |
| const std::string metric_name_; |
| const std::string attribute_name_; |
| std::map<AttributeType, int64_t> values_; |
| }; |
| |
| } // namespace android |
| |
| #endif // ANDROID_COUNTER_METRIC_H_ |