Cassandra rapid prototyping with achilles
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The document discusses Achilles, an open source Java library that provides an object mapping layer for Apache Cassandra. It allows for rapid prototyping with Cassandra by providing a concise API for CRUD operations, queries, validation, batch processing and more. The document outlines Achilles' main features and capabilities, provides code examples, and invites the reader to learn more and download Achilles from their website.
Cassandra rapid prototyping with achilles
- 1. Cassandra rapid prototyping with Achilles www.achilles.io 1 @doanduyhai
- 2. DuyHai DOAN Java/Cassandra freelance developer ! ! Daytime: + ! ! At night: + www.achilles.io 2 @doanduyhai
- 3. What is Achilles ? Yet another C* object mapper www.achilles.io 3 @doanduyhai
- 4. What is Achilles ? More than a C* object mapper www.achilles.io 4 @doanduyhai
- 5. Demo TDD with Achilles www.achilles.io 5 @doanduyhai
- 6. Main API •manager.insert(entity) ! •manager.update(managedEntity) ! •manager.remove(entity) ! •manager.find(Entity.class, primaryKey) www.achilles.io 6 @doanduyhai
- 7. Thread safety for persistence manager No JOINS means www.achilles.io 7 @doanduyhai
- 8. Thread safety for persistence manager No JOINS means ! ! No complex object graph www.achilles.io 8 @doanduyhai
- 9. Thread safety for persistence manager No JOINS means ! ! No complex object graph ! ! No state to keep www.achilles.io 9 @doanduyhai
- 10. What’s about proxy ? proxifiedEntity = manager.find(Entity.class, primaryKey) Dirty check www.achilles.io 10 @doanduyhai ProxifiedEntity Real Entity State Setters interception
- 11. Why proxies ? emc² Albert EINSTEIN GERMANY User einstein = manager.find(User.class,”emc²”); ! einstein.setCountry(“USA”); ! manager.insert(einstein); emc² Albert EINSTEIN GERMANY emc² Albert EINSTEIN USA www.achilles.io 11 @doanduyhai Waste of space !!
- 12. Why proxies ? emc² Albert EINSTEIN GERMANY User einstein = manager.find(User.class,”emc²”); ! einstein.setCountry(“USA”); ! manager.update(einstein); emc² Albert EINSTEIN GERMANY USA www.achilles.io 12 @doanduyhai
- 13. Slice query List<Message> entities = manager.sliceQuery(Message.class) .forSelect() .withPartitionComponents(10L) .fromClusterings(“forums”).toClusterings(“forums”, uuid1) .limit(10).fromInclusiveToExclusiveBounds() .get(); SELECT * FROM Message WHERE user_id = 10 AND (message_folder) ≥ (‘forums’) AND (message_folder, date) < (‘forums’, uuid1) ORDER BY message_folder ASC LIMIT 10; www.achilles.io 13 @doanduyhai
- 14. Typed query RegularStatement select = select().from(“user_messages”) .where(eq(“user_id”,bindMarker())) .and(gte(asList(“message_folder”), bindMarker())) .and(lt(asList(“message_folder”, “date”), bindMarker())) .limit(10); ! List<Message> messages = manager.typedQuery(Message.class, select, userId, asList(“forums”), asList(“forums”, uuid1)) .get(); www.achilles.io 14 @doanduyhai
- 15. Native query RegularStatement nativeQuery = new SimpleStatement(“SELECT * FROM Message WHERE … LIMIT 20”); ! List<TypedMap> messages = manager.nativeQuery(nativeQuery).get(); ! TypedMap firstMessage = messages.get(0); ! // with normal Map<String, Object> // String interlocutor = (String) map.get(“interlocutor”); ! String interlocutor = firstMessage.getTyped(“interlocutor”); String interlocutor = firstMessage.<String>getTyped(“interlocutor”); www.achilles.io 15 @doanduyhai
- 16. Counter API Special proxy type www.achilles.io 16 @doanduyhai public Long get(); ! public void incr(); ! public void incr(Long increment); ! public void decr(); ! public void decr(Long decrement);
- 17. Options •Setting C* special options •Apply to main API insert(), update(), remove() … www.achilles.io 17 @doanduyhai manager.insert(user, OptionsBuilder .withConsistency(QUORUM) .ttl(10) .timestamp(1357949499999L) .ifNotExists() );
- 18. Lifecycle interceptors Hooks into persistence lifecycle www.achilles.io 18 @doanduyhai public interface Interceptor<T> { public void onEvent(T entity); public List<Event> events(); } ! public enum Event { PRE_PERSIST, POST_PERSIST, PRE_UPDATE, POST_UPDATE, PRE_REMOVE, POST_REMOVE, POST_LOAD; }
- 19. Bean Validation (JSR-303) Just a built-in interceptor, PRE_PERSIST, PRE_UPDATE @Entity(table = “entity”) public class Entity { @Id private Long id; ! @Column @NotEmpty private String name; } www.achilles.io 19 @doanduyhai
- 20. Batch mode C* 2.0 atomic batches Batch batch = manager.createBatch(); ! batch.startBatch(); ! batch.insert(new Entity(…..)); batch.update(…..); batch.remove(…..); batch.removeById(MyEntity.class, primaryKey); ! batch.endBatch(); www.achilles.io 20 @doanduyhai
- 21. Documentation •Comprehensive Github WIKI ! •Twitter-clone demo app (demo.achilles.io) ! •Versioned documentation (HTML & PDF) ! •JavaDoc www.achilles.io 21 @doanduyhai
- 22. Documentation www.achilles.io 22 @doanduyhai
- 23. Asynchronous •Available for ➡ main API ( insert(), update(), …) ➡ slice queries ➡ typed & native queries www.achilles.io 23 @doanduyhai
- 24. Roadmap for future •C* 2.1 user defined types (UDT) & tuples ! •Reactive programming (RxJava) ! •Transparent search integration (ElasticSearch, Solr…) www.achilles.io 24 @doanduyhai
- 25. Where to download ? •www.achilles.io ! •Google “Achilles Cassandra” ☞ first result www.achilles.io 25 @doanduyhai
- 26. Take away •More than a simple object mapper ! •Productivity-oriented ! •KISS ! •Documented www.achilles.io 26 @doanduyhai
- 27. ! " Q & A www.achilles.io 27 @doanduyhai