You can read about Twitter snowflake here.
The IDs are 64-bits in size and are generated with the combination of the following:
- Epoch timestamp in milliseconds precision - 41 bits. The maximum timestamp that can be represented using 41 bits is
2^41 - 1, or2199023255551, That gives us 69 years with respect to a custom epoch.. - Node ID - 10 bits. This gives us 1024 nodes/machines.
- Local counter per machine - 12 bits. The counter’s max value would be 4095.
The Snowflake class should be used as a singleton in your application.
SnowflakeIdGenerator s = new SnowflakeIdGenerator(275)
s.nextId()Read the blog to understand more: