In some use cases, a bolt needs to cache the data for a few seconds before performing some operation, such as cleaning the cache after every 5 seconds or inserting a batch of records into a database in a single request.
The tick tuple is the system-generated (Storm-generated) tuple that we can configure at each bolt level. The developer can configure the tick tuple at the code level while writing a bolt.
We need to overwrite the following method in the bolt to enable the tick tuple:
@Override
public Map<String, Object> getComponentConfiguration() {
Config conf = new Config();
int tickFrequencyInSeconds = 10;
conf.put(Config.TOPOLOGY_TICK_TUPLE_FREQ_SECS,
tickFrequencyInSeconds);
return conf;
} In the preceding code, we have configured the tick tuple time to 10 seconds. Now, Storm will start generating a tick tuple after every 10 seconds.
Also, we need to add the following code in the execute method of the bolt to identify the type of tuple:
@Override public...
