Creating fault tolerant system - Use data file to reload save data?

Question

EDIT - The implementation Language is Java.

I want to make a simple fault tolerant system.

• Object A - This object contains the decision logic for the system.
• Object B - This object will be used control the fault tolerance

My initial ideas are to have object A update object B with the value of variables that are to be saved to a data file. Then object B will create a data file that will be saved to a hard drive of the platform system.

My question is: how would I create a data file using the values of object variables and then retrieve those variables from the data file? when they are called.

I am happy just to write variable values to a notepad file and then recall them from the file

Answer 1

For simple use cases where you just want to provide persistence and fault tolerance for in-memory data, you might want to have a look at Prevayler. It's a straightforward library that builds checkpoints (snapshots) and redo journaling on top of serialization, giving you transactional semantics on the cheap.