SampleSet -> HistogramSamples (will be reused by SparseHistogram)

base/metrics/sample_vector.h

+// 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.
+
+// SampleVector implements HistogramSamples interface. It is used by all
+// Histogram based classes to store samples.
+
+#ifndef BASE_METRICS_SAMPLE_VECTOR_H_
+#define BASE_METRICS_SAMPLE_VECTOR_H_
+
+#include <vector>
+
+#include "base/compiler_specific.h"
+#include "base/gtest_prod_util.h"
+#include "base/memory/scoped_ptr.h"
+#include "base/metrics/histogram_base.h"
+#include "base/metrics/histogram_samples.h"
+
+namespace base {
+
+class BucketRanges;
+
+class BASE_EXPORT_PRIVATE SampleVector : public HistogramSamples {
+ public:
+  explicit SampleVector(const BucketRanges* bucket_ranges);
+  virtual ~SampleVector();
+
+  // HistogramSamples implementation:
+  virtual void Accumulate(HistogramBase::Sample value,
+                          HistogramBase::Count count) OVERRIDE;
+  virtual HistogramBase::Count GetCount(
+      HistogramBase::Sample value) const OVERRIDE;
+  virtual HistogramBase::Count TotalCount() const OVERRIDE;
+  virtual scoped_ptr<SampleCountIterator> Iterator() const OVERRIDE;
+
+  // Get count of a specific bucket.
+  HistogramBase::Count GetCountAtIndex(size_t bucket_index) const;
+
+ protected:
+  virtual bool AddSubtractImpl(
+      SampleCountIterator* iter,
+      HistogramSamples::Instruction instruction) OVERRIDE;
+
+  virtual size_t GetBucketIndex(HistogramBase::Sample value) const;
+
+ private:
+  FRIEND_TEST_ALL_PREFIXES(HistogramTest, CorruptSampleCounts);
+
+  std::vector<HistogramBase::Count> counts_;
+
+  // Shares the same BucketRanges with Histogram object.
+  const BucketRanges* const bucket_ranges_;
+
+  DISALLOW_COPY_AND_ASSIGN(SampleVector);
+};
+
+class BASE_EXPORT_PRIVATE SampleVectorIterator : public SampleCountIterator {
+ public:
+  SampleVectorIterator(const std::vector<HistogramBase::Count>* counts,
+                       const BucketRanges* bucket_ranges);
+
+  // SampleCountIterator implementation:
+  virtual bool Done() const OVERRIDE;
+  virtual void Next() OVERRIDE;
+  virtual void Get(HistogramBase::Sample* min,
+                   HistogramBase::Sample* max,
+                   HistogramBase::Count* count) const OVERRIDE;
+  virtual bool GetBucketIndex(size_t* index) const OVERRIDE;
+
+ private:
+  void SkipEmptyBuckets();
+
+  const std::vector<HistogramBase::Count>* counts_;
+  const BucketRanges* bucket_ranges_;
+
+  size_t index_;
+};
+
+}  // namespace base
+
+#endif  // BASE_METRICS_SAMPLE_VECTOR_H_