Refactors DeviceOrientation to make it more extensible

content/browser/device_orientation/data_fetcher_impl_android.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.
 
 #ifndef CHROME_BROWSER_DEVICE_ORIENTATION_DATA_FETCHER_IMPL_ANDROID_H_
 #define CHROME_BROWSER_DEVICE_ORIENTATION_DATA_FETCHER_IMPL_ANDROID_H_
 
 #include <jni.h>
 
 #include "base/memory/scoped_ptr.h"
 #include "base/synchronization/lock.h"
 #include "content/browser/device_orientation/data_fetcher.h"
-#include "content/browser/device_orientation/orientation.h"
+#include "content/browser/device_orientation/device_data.h"
 
 namespace device_orientation {
 
+class Orientation;
+
 // Android implementation of DeviceOrientation API.
 
 // Android's SensorManager has a push API, whereas Chrome wants to pull data.
 // To fit them together, we store incoming sensor events in a 1-element buffer.
 // SensorManager calls SetOrientation() which pushes a new value (discarding the
-// previous value if any). Chrome calls GetOrientation() which reads the most
-// recent value. Repeated calls to GetOrientation() will return the same value.
+// previous value if any). Chrome calls GetDeviceData() which reads the most
+// recent value. Repeated calls to GetDeviceData() will return the same value.
 
 class DataFetcherImplAndroid : public DataFetcher {
  public:
   // Must be called at startup, before Create().
   static void Init(JNIEnv* env);
 
   // Factory function. We'll listen for events for the lifetime of this object.
   // Returns NULL on error.
   static DataFetcher* Create();
 
   virtual ~DataFetcherImplAndroid();
 
   // Called from Java via JNI.
   void GotOrientation(JNIEnv*, jobject,
                       double alpha, double beta, double gamma);
 
   // Implementation of DataFetcher.
-  virtual bool GetOrientation(Orientation* orientation) OVERRIDE;
+  virtual const DeviceData* GetDeviceData(DeviceData::Type type) OVERRIDE;
 
  private:
   DataFetcherImplAndroid();
+  const Orientation* GetOrientation();
 
   // Wrappers for JNI methods.
   bool Start(int rate_in_milliseconds);
   void Stop();
 
-  // Value returned by GetOrientation.
+  // Value returned by GetDeviceData.
   scoped_ptr<Orientation> current_orientation_;

[hans, 2012/08/03 13:05:41]

should this be a scoped_refptr?

[aousterh, 2012/08/03 13:42:18]

Done.

 
-  // 1-element buffer, written by GotOrientation, read by GetOrientation.
+  // 1-element buffer, written by GotOrientation, read by GetDeviceData.
   base::Lock next_orientation_lock_;
   scoped_ptr<Orientation> next_orientation_;
 
   DISALLOW_COPY_AND_ASSIGN(DataFetcherImplAndroid);
 };
 
 }  // namespace device_orientation
 
 #endif  // CHROME_BROWSER_DEVICE_ORIENTATION_DATA_FETCHER_IMPL_ANDROID_H_