No, this is not correct. The id generation service works in the same way that Hibernate's sequence generator does. Each host connects to the database and says "give me a batch of IDs that nobody else knows about, then increment the database". In the case you presented, Host 1 would grab a batch of ids 100-149 and then Host 2 would grab a batch of IDs 150-199, etc etc. The logic for doing this is in the dao, IdGenerationDaoImpl.findNextId() which the service uses.
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