| // Copyright (c) 2012 The Chromium Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #ifndef BASE_METRICS_SPARSE_HISTOGRAM_H_ |
| #define BASE_METRICS_SPARSE_HISTOGRAM_H_ |
| |
| #include <map> |
| #include <string> |
| |
| #include "base/base_export.h" |
| #include "base/basictypes.h" |
| #include "base/compiler_specific.h" |
| #include "base/memory/scoped_ptr.h" |
| #include "base/metrics/histogram_base.h" |
| #include "base/synchronization/lock.h" |
| |
| namespace base { |
| |
| class HistogramSamples; |
| |
| class BASE_EXPORT_PRIVATE SparseHistogram : public HistogramBase { |
| public: |
| // If there's one with same name, return the existing one. If not, create a |
| // new one. |
| static HistogramBase* FactoryGet(const std::string& name, int32 flags); |
| |
| virtual ~SparseHistogram(); |
| |
| // HistogramBase implementation: |
| virtual HistogramType GetHistogramType() const OVERRIDE; |
| virtual bool HasConstructionArguments(Sample minimum, |
| Sample maximum, |
| size_t bucket_count) const OVERRIDE; |
| virtual void Add(Sample value) OVERRIDE; |
| virtual void WriteHTMLGraph(std::string* output) const OVERRIDE; |
| virtual void WriteAscii(std::string* output) const OVERRIDE; |
| virtual scoped_ptr<HistogramSamples> SnapshotSamples() const OVERRIDE; |
| |
| private: |
| // Clients should always use FactoryGet to create SparseHistogram. |
| SparseHistogram(const std::string& name); |
| |
| virtual void GetParameters(DictionaryValue* params) const OVERRIDE; |
| virtual void GetCountAndBucketData(Count* count, |
| ListValue* buckets) const OVERRIDE; |
| |
| friend class SparseHistogramTest; // For constuctor calling. |
| |
| // Protects access to |sample_counts_| and |redundant_count_|. |
| mutable base::Lock lock_; |
| std::map<HistogramBase::Sample, HistogramBase::Count> sample_counts_; |
| HistogramBase::Count redundant_count_; |
| |
| DISALLOW_COPY_AND_ASSIGN(SparseHistogram); |
| }; |
| |
| } // namespace base |
| |
| #endif // BASE_METRICS_SPARSE_HISTOGRAM_H_ |