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I want to be able to monitor events of cache creation in Apache Ignite.

Whenever such events happen - I want to be able to do something with those caches, after they are created, but before anyone else could inserts something.

So I used local listener. Below is all the code:

import org.apache.ignite.Ignite;
import org.apache.ignite.IgniteCache;
import org.apache.ignite.Ignition;
import org.apache.ignite.configuration.IgniteConfiguration;
import org.apache.ignite.events.CacheEvent;
import org.apache.ignite.events.EventType;
import org.apache.ignite.lang.IgnitePredicate;
import org.apache.ignite.resources.IgniteInstanceResource;
import org.springframework.context.annotation.Configuration;
import org.springframework.core.env.Environment;

@Configuration
public class ServerConfig 

 public ServerConfig(Environment e) throws Exception 
 IgniteConfiguration cfg = new IgniteConfiguration();
 cfg.setIncludeEventTypes(EventType.EVT_CACHE_STARTED);
 Ignite ignite = Ignition.start(cfg);
 String cacheName = "test";

 registerCacheCreationListener(ignite);
 IgniteCache<Integer, String> cache = ignite.getOrCreateCache(cacheName);
 

 private void registerCacheCreationListener(Ignite ignite)
 IgnitePredicate<CacheEvent> locLsnr = new IgnitePredicate<CacheEvent>()
 @IgniteInstanceResource
 private Ignite ignite;
 @Override
 public boolean apply(CacheEvent evt) 
 System.out.println("Received event [evt=" + evt.name() + " cacheName=" + evt.cacheName());
 IgniteCache<Integer, String > cache = ignite.cache(evt.cacheName()); // CANNOT ACCESS evt.cacheName() - STUCKS HERE
 System.out.println("finish listener");
 return true;
 
 ;
 ignite.events().localListen(locLsnr, EventType.EVT_CACHE_STARTED);
 

So when I do:

ignite.cache(evt.cacheName())

inside IgnitePredicate - it is not yet available as I understand.

Please help me find out where can I be wrong.
Thanks.

As a rule you should not perform cache operations, or most of other operations that block or access Ignite internals. Events should be very fast and lightweight, meaning that they are executed from inside Ignite threads and Ignite internal locks.

Just schedule an operation in a different thread on event arrival.