This document summarizes a presentation on Spring Data by Eric Bottard and Florent Biville. Spring Data aims to provide a consistent programming model for new data stores while retaining store-specific features. It uses conventions over configuration for mapping objects to data stores. Repositories provide basic CRUD functionality without implementations. Magic finders allow querying by properties. Pagination and sorting are also supported.

1. Hands On Spring Data
Eric Bottard, Developer Advocate, VMware
@ebottard
Florent Biville, Developer, Lateral Thoughts
@fbiville
© 2012 SpringSource, by VMware

2. Eric BOTTARD
• Developer Advocate VMware
• @ebottard
• ebottard@vmware.com
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3. Florent BIVILLE
• Développeur chez LateralThoughts
• @fbiville
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4. “ Spring Data is an umbrella project which
aims to provide a familiar and consistent
Spring-based programming model for for
new datastores while retaining store-
specific features and capabilities

5. Relational
JDBC
JPA

6. Document store
MongoDB
CouchDB

7. Column oriented
HBase
Cassandra

8. Graph
Neo4j
OrientDB

9. Data Grids
GemFire
Coherence
Terracotta

10. Key Value
Redis
Riak

11. Big Data
Hadoop

12. Templates

13. Mapping

14. Mapping
• Tells the framework how to store object properties and
relationships
• Favors convention over configuration
• Does not try to shoehorn one model into another (e.g.
does not use JPA annotations for Mongo)
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15. Example: MongoDB
@Document
@CompoundIndexes({
@CompoundIndex(name = "age_idx", def = "{'lastName': 1, 'age': -1}")
})
public class Person<T extends Address> {
@Id
private String id;
@Indexed(unique = true)
private Integer ssn;
@Field("fName")
private String firstName;
@Indexed
private String lastName;
@Transient
private Integer accountTotal;
@DBRef
private List<Account> accounts;
private T address;

16. Repositories

17. Repositories
public interface PersonRepository
extends CrudRepository<User, Long> {
…
}
No implementation needed!

18. Magic Finders

19. Magic Finders
public interface PersonRepository extends Repository<User, Long> {
List<Person> findByEmailAddressAndLastname(EmailAddress emailAddress, String
lastname);
// Enables the distinct flag for the query
List<Person> findDistinctPeopleByLastnameOrFirstname(String lastname, String
firstname);
List<Person> findPeopleDistinctByLastnameOrFirstname(String lastname, String
firstname);
// Enabling ignoring case for an individual property
List<Person> findByLastnameIgnoreCase(String lastname);
// Enabling ignoring case for all suitable properties
List<Person> findByLastnameAndFirstnameAllIgnoreCase(String lastname, String
firstname);
// Enabling static ORDER BY for a query
List<Person> findByLastnameOrderByFirstnameAsc(String lastname);
List<Person> findByLastnameOrderByFirstnameDesc(String lastname);
}

20. Pagination

21. Pagination and Dynamic Ordering
public interface PersonRepository
extends CrudRepository<User, Long> {
Page<User> findByLastname(String lastname, Pageable pageable);
List<User> findByLastname(String lastname, Sort sort);
// NOTE: Pageable embeds a Sort
}

22. Qu eries

23. Explicit Queries
public interface ProductsRepository extends JpaRepository<Product, Long> {
@Query(value = "select p from Product p order by p.rating desc",
countQuery = "select count(p) from Product p")
Page<Product> findTopRated(Pageable pageable);
}

24. Cross Store support

25. Query DSL Integration

26. REST

27. REST Shell

28. Customization

30. JSON

31. Mongo DB - schema-less document DB
databases
mongo> show dbs;
myDatabase 0.3046578 GB
mongo> use myDatabase;
collections
mongo> show collections;
rockCollection
colleagueSean
mongo> db.rockCollection.find().pretty(); // last call “prettifies” output
documents
mongo> db.rockCollection.find({name:"The Beatles"}).pretty();
{"_id" : ObjectId("50b7d870744e5ef5eee5224e"),
"_class" : "xxx.music.domain.Band",
"name" : "The Beatles",
[...] }

32. MongoDB: Queries as JSON documents
db.inventory.find({
price:1.99,
$or: [
{ qty: { $lt: 20 } },
{ sale: true }
]
})

33. GridFS - can I haz large objectz?
• mongo> show collections;
– fs.chunks
– fs.files
• CHUNKS
– 256KB portion of a Mongo object (a.k.a. file), stored into
collection “fs.chunks”
• FILES
– Metadata about the file stored into “fs.files”: filename, content
type ...
• Spring Data brings
– GridFsTemplate
– GridFsResource (wraps GridFSDBFile)
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35. Nodes & Relationships
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36. Nodes
NoSQL
Spring HELPS_WITH standsFor: "Not Only
Data how: "it roxx" SQL"
IS_PART_OF
Properties
Relationship
Spring

37. Cypher

38. Neo4J - Cypher Query Language
start doctor=node:characters(character = 'Doctor')
match (doctor)<-[:COMPANION_OF]-(companion)
-[:APPEARED_IN]->(episode)
return companion.character, count(episode)
order by count(episode) desc
limit 5

39. Image credits
• keys http://www.sxc.hu/photo/1381979
• spiderweb http://www.sxc.hu/photo/1309629
• columns http://www.sxc.hu/photo/511217
• documents http://www.sxc.hu/photo/913588
• umbrella http://www.sxc.hu/photo/1182110
• nail http://www.sxc.hu/photo/1101239
• relational http://www.sxc.hu/photo/541351
• callback http://www.sxc.hu/photo/1134440
• repositories http://www.sxc.hu/photo/1352633
• pagination http://www.sxc.hu/photo/830250
• magic http://www.sxc.hu/photo/829135
• cypher http://www.sxc.hu/photo/1118342
• mapping http://www.sxc.hu/photo/1147986
• grid http://www.sxc.hu/photo/1222068
• elephant http://www.sxc.hu/photo/1168187
• cross knot http://www.sxc.hu/photo/1396427
• rope knot http://www.sxc.hu/photo/1181983
• married http://www.sxc.hu/photo/937988
• shell http://www.sxc.hu/photo/866402
• diesel http://www.sxc.hu/photo/1076436
• car tuning http://www.sxc.hu/photo/5877
• rest on couch: If you haven’t, go watch Fight Club. NOW.
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