How to remotely synchronize two sets?

Question

I need to synchronize two large sets of strings in Java, one of the on the client and the other on the server. Most probably the client is missing a couple of entries which it should receive from the server. I don't want to transfer all members, I want to minimize the communication and the computation on the server (the client may work harder).

Any idea besides divide-and-conquer?

I'm not asking about the communication technology or alike, I'm only interested in a good algorithm. I think something like what version control does would be optimal, but I'm afraid I can't do it this way.

Each has it's own set and changes can go both ways. Conflicts are improbable and quite irrelevant. — maaartinus, Mar 14 '11 at 10:32
is this like hub & spoke where the server's changes are likely due to some other clients' changes — Ron, Mar 15 '11 at 16:18
@Ron Some of them. The server drops some data, too. I'm afraid I need to think more about what exactly happens. — maaartinus, Mar 17 '11 at 22:09

score 3 · Accepted Answer · answered Mar 14 '11 at 04:43

3

You can keep a generation counter for the set on the server along with a change log for each generation. The client can request all changes since the last synchronization. It can then integrate those changes and also (if applicable) send back any remaining client-side changes since the last synchronization.

answered Mar 14 '11 at 04:43

Ted Hopp

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I'm not sure if this is the right thing to do, I need to think more about it. But for the question as stated you gave the right answer. – maaartinus Mar 22 '11 at 21:29

score 1 · Answer 2 · answered Mar 14 '11 at 04:37

1

you can use socket, at first synchronize all members ans then using custom methods which add and remove members in local set and send data+instruction to other end you can also use jmx active mq

answered Mar 14 '11 at 04:37

Nirmal- thInk beYond

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How to remotely synchronize two sets?

2 Answers2