The document discusses Hazelcast, an open source in-memory data grid (IMDG) for Java. It provides an overview of Hazelcast features such as distributed caching, computing, and persistence. It also covers how to get started with Hazelcast including downloading, configuration, and code samples. The presentation encourages attendees to try Hazelcast for tasks such as scaling NoSQL/RDBMS, compute-intensive jobs, and web session replication.

1. @dbrimley#DevoxxHazelcast
High Performance In-Memory Java with Open
Source
David Brimley
@dbrimley
http://blog.hazelcast.com/
http://www.hazelcast.org/

2. @dbrimley#DevoxxHazelcast
Who is this guy?
• Senior Solutions Architect for Hazelcast.
• 17 Years Java Development.
• Started out as a Cobol Programmer in 1988.
• Learnt to code Basic on a Vic-20 and BBC Model B.
• Oracle Coherence and Pivotal Gemfire.

3. @dbrimley#DevoxxHazelcast
In Memory Java
• High Performance In Memory Java? It’s an IMDG!
• Getting to grips with Hazelcast, a tour of features.
• Some IMDG Tips!

4. @dbrimley#DevoxxHazelcast
In Memory Java
• It’s 2 things really, the 2 C.
• Cache
• Compute
• The Magic is the D you stick in front…Distributed!
• DCache + DCompute = IMDG!

5. @dbrimley#DevoxxHazelcast
Evolution of IMDG
CACHE IN ONE PROCESS - A MAP, AGGHH OOM!

6. @dbrimley#DevoxxHazelcast
Evolution of IMDG
CACHE IN ONE PROCESS - WITH EVICTION

7. @dbrimley#DevoxxHazelcast
Evolution of IMDG
DISTRIBUTED CACHE

8. @dbrimley#DevoxxHazelcast
Evolution of IMDG
DISTRIBUTED COMPUTE

9. @dbrimley#DevoxxHazelcast
Evolution of IMDG
BIG DATA IMDG

10. @dbrimley#DevoxxHazelcast
Qualities of an IMDG
• It should be easy to scale, vertically and horizontally.
• It should be fault tolerant.
• It should be performant.
• It should have a easy to understand API.

11. @dbrimley#DevoxxHazelcast
Enter Hazelcast!
• Java Collections & Queues - Distributed!
• Java Concurrency - Distributed!
• Persist to and Read from from Anything!
(RDBMS,File,Hadoop,Cassandra,MongoDB)
• Predicate and SQL like queries!
• Topics(Pub/Sub)
• Rich Event Callbacks

12. @dbrimley#DevoxxHazelcast
<dependency>
<groupId>com.hazelcast</groupId>
<artifactId>hazelcast</artifactId>
<version>3.2.2</version>
</dependency>
1. Starting a Hazelcast Cluster Node

13. @dbrimley#DevoxxHazelcast
HazelcastInstance hz = Hazelcast.newHazelcastInstance();
2. Starting a Hazelcast Cluster Node

14. @YourTwitterHandle@dbrimley#DevoxxHazelcast
D
em
o

15. @dbrimley#DevoxxHazelcast
Distributed Compute
• Executors
• EntryProcessor
• MapReduce

16. @dbrimley#DevoxxHazelcast
Executor can run anywhere
• IExecutorService
• Runnable or Callable
• Targeted execution in the grid (keys,members)

17. @dbrimley#DevoxxHazelcast
HazelcastInstance hz = Hazelcast.newHazelcastInstance();
IExecutorService executor = hz.getExecutorService(“myEService");
executor.execute(new EchoTask("foo"));
2. Java Executor, but Distributed!

18. @dbrimley#DevoxxHazelcast
EntryProcessor
• Execute your code on an entry in an atomic way.
• You do not need any explicit lock on entry.
• Runs via IMap.

19. @dbrimley#DevoxxHazelcast
/**
* Applies the user defined EntryProcessor to the entry mapped
by the key.
* Returns the the object which is result of the process()
method of EntryProcessor.
*/
Object executeOnKey(K key, EntryProcessor entryProcessor);
EntryProcessor via IMap

20. @dbrimley#DevoxxHazelcast
MapReduce
• New in 3.2
• Hadoop like API.
• Aggregators in 3.3
• Scheduled Tasks in 3.4

21. @dbrimley#DevoxxHazelcast
IMap<String,String> map = hazelcastInstance.getMap("articles");
KeyValueSource<String,String> source =
KeyValueSource.fromMap(map);
Job<String, String> job = jobTracker.newJob( source );
ICompletableFuture<Map<String, Long>> future = job
.mapper( new TokenizerMapper() )
.combiner( new WordCountCombinerFactory() )
.reducer( new WordCountReducerFactory() )
.submit();
MapReduce

22. @dbrimley#DevoxxHazelcast
Persist and Read from anywhere.
• Implement a MapStore interface.
• Configure your Map.
• Cache misses will read through to the store.
• Cache updates can persist to store (sync/async).

23. @dbrimley#DevoxxHazelcast
<map name="aDistributedMap">
<map-store enabled="true">
<class-name>com.company.YourMapStore</class-name>
<write-delay-seconds>30</write-delay-seconds>
</map-store>
<indexes>
<index ordered="true">aValueProperty</index>
</indexes>
</map>
2. Configure (in XML,Spring or API)

24. @dbrimley#DevoxxHazelcast
public class UserMapStore implements MapStore<Integer, User> {
public void store(Integer userKey, User user) {
userDao.insertUser(user);
}
public User load(Integer userKey) {
return userDao.getUser(userKey);
}
…… (more methods like delete, loadAll)
2. Implement MapStore

25. @dbrimley#DevoxxHazelcast
We like standards.
• Greg Luck, Hazelcast CTO is JSR107 co-spec lead.
• Hazelcast will be JSR107 compliant this summer.
• https://github.com/hazelcast/hazelcast/tree/
jcache-preview

26. @YourTwitterHandle@dbrimley#DevoxxHazelcast
D
em
o

27. @dbrimley#DevoxxHazelcast
Some IMDG Advice
• Don’t force in your RDBMS schema.
• Do you really need that transaction?
• Execute near the data.
• Use the right Serialisation interface.
• Tune your JVM.

28. @YourTwitterHandle#DVXFR14{session hashtag} @dbrimley#DevoxxHazelcast
Sum
m
ary

29. @dbrimley#DevoxxHazelcast
Powerful tool for many Use Cases
• Unscalable NoSQL or RDBMS fix.
• Compute Intensive Tasks
• Web Session Replication
• HA Services
• WAN Replication

30. @dbrimley#DevoxxHazelcast
Get Coding!
• hazelcast.org - for open source and downloads
• hazelcast.com - for pro support,papers & webinars
• github.com/hazelcast for sources
• github.com/hazelcast/hazelcast-code-samples
• follow me on twitter @dbrimley

31. @YourTwitterHandle#DVXFR14{session hashtag} @dbrimley#DevoxxHazelcast
Q
&
A

32. @dbrimley#DevoxxHazelcast
Thanks / Creative Commons
•Presentation Template — Guillaume LaForge
•The Queen — A prestigious heritage with some
inspiration from The Sex Pistols and funny Devoxxians
•Girl with a Balloon — Banksy
•Tube — Michael Keen