/**
* Reads a stably logged update (a serializable object) from a stream. This callback is invoked
* during recovery, once for every record in the log. After reading the update, this method
* invokes the applyUpdate (abstract) method in order to obtain the new snapshot value. It then
* returns the new snapshot.
*
* @param in the input stream
* @param state the current state
* @return the new state
* @exception Exception can raise any exception
*/
public Object readUpdate(LogInputStream in, Object state) throws Exception {
MarshalInputStream s = new MarshalInputStream(in);
return applyUpdate(s.readObject(), state);
}
/**
* Read the snapshot object from a stream and returns the snapshot. This callback is invoked when
* the client calls the recover method of ReliableLog.
*
* @param in the input stream
* @return the state (snapshot)
* @exception Exception can raise any exception
*/
public Object recover(InputStream in) throws Exception {
MarshalInputStream s = new MarshalInputStream(in);
return s.readObject();
}