| 69 |  | delete previousSnapshot_; | 
| 70 |  | } | 
| 71 |  |  | 
| 72 | < | virtual bool advance() {} | 
| 72 | > | virtual bool advance() { return true; } | 
| 73 |  |  | 
| 74 |  | virtual Snapshot* getSnapshot(int id) = 0; | 
| 75 |  |  | 
| 93 |  | return storageLayout_; | 
| 94 |  | } | 
| 95 |  |  | 
| 96 | < | protected: | 
| 96 | > | private: | 
| 97 | > | int storageLayout_; | 
| 98 |  |  | 
| 99 | + | protected: | 
| 100 | + |  | 
| 101 |  | SnapshotManager(int storageLayout) : storageLayout_(storageLayout), currentSnapshot_(NULL), previousSnapshot_(NULL) { | 
| 102 |  | } | 
| 103 |  |  | 
| 104 |  | Snapshot* currentSnapshot_; | 
| 105 |  | Snapshot* previousSnapshot_; | 
| 106 |  |  | 
| 104 | – | private: | 
| 105 | – | int storageLayout_; | 
| 107 |  |  | 
| 108 |  | }; | 
| 109 |  |  |