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.

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
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@doanduyhai

4. What is Achilles ?
More than a C* object mapper
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@doanduyhai

5. Demo
TDD with Achilles
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6. Main API
•manager.insert(entity)
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•manager.update(managedEntity)
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•manager.remove(entity)
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•manager.find(Entity.class, primaryKey)
www.achilles.io 6
@doanduyhai

7. Thread safety for persistence manager
No JOINS means
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8. Thread safety for persistence manager
No JOINS means
!
!
No complex object graph
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@doanduyhai

9. Thread safety for persistence manager
No JOINS means
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No complex object graph
!
!
No state to keep
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10. What’s about proxy ?
proxifiedEntity = manager.find(Entity.class, primaryKey)
Dirty check
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@doanduyhai
ProxifiedEntity
Real
Entity
State
Setters interception

11. Why proxies ?
emc² Albert EINSTEIN GERMANY
User einstein = manager.find(User.class,”emc²”);
!
einstein.setCountry(“USA”);
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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);
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// with normal Map<String, Object>
// String interlocutor = (String) map.get(“interlocutor”);
!
String interlocutor = firstMessage.getTyped(“interlocutor”);
String interlocutor = firstMessage.<String>getTyped(“interlocutor”);
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16. Counter API
Special proxy type
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public Long get();
!
public void incr();
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public void incr(Long increment);
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public void decr();
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public void decr(Long decrement);

17. Options
•Setting C* special options
•Apply to main API insert(), update(), remove() …
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@doanduyhai
manager.insert(user,
OptionsBuilder
.withConsistency(QUORUM)
.ttl(10)
.timestamp(1357949499999L)
.ifNotExists()
);

18. Lifecycle interceptors
Hooks into persistence lifecycle
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@doanduyhai
public interface Interceptor<T> {
public void onEvent(T entity);
public List<Event> events();
}
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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();
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batch.startBatch();
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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
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•Twitter-clone demo app (demo.achilles.io)
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•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
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•Reactive programming (RxJava)
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•Transparent search integration (ElasticSearch, Solr…)
www.achilles.io 24
@doanduyhai

25. Where to download ?
•www.achilles.io
!
•Google “Achilles Cassandra” ☞ first result
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@doanduyhai

26. Take away
•More than a simple object mapper
!
•Productivity-oriented
!
•KISS
!
•Documented
www.achilles.io 26
@doanduyhai

27. ! "
Q & A
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