Alexey Zinoviev presented this paper on the Joker'15 conference http://jokerconf.com/talks/zynovyev/ This paper covers next topics: Java, Morphia, Hibernate OGM, JPA, Spring Data, Kundera, NoSQL, Mongo, Jongo

1. Java straitjackets for
MongoDB
Alexey Zinovyev, Java Trainer

2. About
I am a <graph theory, machine learning,
traffic jams prediction, BigData algorithms>
scientist
But I'm a <Java, NoSQL, Hadoop, Spark>
programmer

3. Raise your hands if you ..
•use Hibernate & Spring

4. Raise your hands if you ..
•use Hibernate & Spring
• keep your data in MongoDB

5. Raise your hands if you ..
•use Hibernate & Spring
• keep your data in MongoDB
• use only Java Driver for Mongo

6. Raise your hands if you ..
•use Hibernate & Spring
• keep your data in MongoDB
• use only Java Driver for Mongo
• write your own mapping from Java objects to
BSON

7. 7Joker 2015
Let’s do this with Mongo’D

8. 8Joker 2015
The Good Old Days

9. 9Joker 2015
One of these fine days...

10. 10Joker 2015
We have a NoSQL job for you, son!

11. 11Joker 2015
But you like SQL and HATE nontraditional data

12. 12Joker 2015
Typical situation, isn’t it?

13. 13Joker 2015
Let’s talk about it, Java - boy...

14. NOSQL

15. 15Joker 2015
What’s the problem with RBDMS’s
• Caching
• Master/Slave
• Cluster
• Table Partitioning
• Sharding

16. 16Joker 2015
Try to find
Mongo

17. 17Joker 2015
Homo
Mongous

18. 18Joker 2015
Fashion and trend

19. 19Joker 2015
Gentle NoSQL
• Scalability

20. 20Joker 2015
Gentle NoSQL
• Scalability
• Nodes and Data Centers

21. 21Joker 2015
Gentle NoSQL
• Scalability
• Nodes and Data Centers
• Easy to add new server

22. 22Joker 2015
Gentle NoSQL
• Scalability
• Nodes and Data Centers
• Easy to add new server
• Specific data model

23. 23Joker 2015
Gentle NoSQL
• Scalability
• Nodes and Data Centers
• Easy to add new server
• Specific data model
• Eventual consistency

24. 24Joker 2015
Comparison criteria
• Education curve
• Performance
• Drivers & frameworks
• Hadoop integration
• Mobile client

25. 25Joker 2015
But what about .. “ACID”?

26. 26Joker 2015
ACID in SQL

27. 27Joker 2015
Atomicity in NoSQL
• read-write-modify (CAS)
• key/row manipulation is atomic
• API for atomic operations
• bad support of transactions (play with 2 phase commit)

28. 28Joker 2015
BASE
• basic availability – all queries will be finished
• soft state – state can be changed without writing
• eventual consistency

29. MONGO DB

30. 30Joker 2015
BSON (something like JSON)
• Adds data types that JSON did not support – (ISO Dates,
ObjectId, etc.)
• Optimized for performance
• Adds compression

31. 31Joker 2015
Mongo: pro and contra
❏ Full-featured query
language
❏ Aggregation framework
❏ Big variety of indexes
❏ Replication and sharding
❏ Documentation
★ Limit for document size
(16 mb)
★ Complex cluster schema
★ No joins

32. 32Joker 2015
Is Mongo terrible?
• Stability?
• JavaScript at the bottom
• Something new
• Low barrier for entry
• Easy to lose your data

33. DBA
programmer

34. 34Joker 2015
The Database and programmers

35. JAVA DRIVER API

36. 36Joker 2015
INSERT
Mongo mongo = new Mongo(…);
DB db = mongo.getDB("myDb");
Collection collection = db.getCollection(“customers");

37. 37Joker 2015
INSERT
Mongo mongo = new Mongo(…);
DB db = mongo.getDB("myDb");
Collection collection = db.getCollection(“customers");
DBObject hotel = new BasicDBObject();
address.put(“name”, “ParkInn”);

38. 38Joker 2015
INSERT
Mongo mongo = new Mongo(…);
DB db = mongo.getDB("myDb");
Collection collection = db.getCollection(“customers");
DBObject hotel = new BasicDBObject();
address.put(“name”, “ParkInn”);
DBObject person = new BasicDBObject();
person.put("firstname”, “Alexey”);
person.put("lastname”, “Zinoviev”);
person.put(“hotel”, hotel);
collection.save(person);

39. 39Joker 2015
SELECT with Filter
DBObject query = new BasicDBObject();
query.put(“hotel.name”, “ParkInn”);
DBCursor cursor = collection.find(query);
for (DBObject element : cursor) {
// Map data onto object
}

40. 40Joker 2015
Async call

41. 41Joker 2015
But.. how about @ and JPA and ..

42. MORPHIA

43. 43Joker 2015
Morphia
Object Document Mapper
• Specifed with annotations
• Implemented with reflection
• Runtime validation

44. 44Joker 2015
Morphia advantages
• Integrated with Spring, Guice and other DI frameworks

45. 45Joker 2015
Morphia advantages
• Integrated with Spring, Guice and other DI frameworks
• Lifecycle Method Annotations (@PrePersist, @PostLoad)

46. 46Joker 2015
Morphia advantages
• Integrated with Spring, Guice and other DI frameworks
• Lifecycle Method Annotations (@PrePersist, @PostLoad)
• Built on top of Mongo Java Driver

47. 47Joker 2015
Morphia advantages
• Integrated with Spring, Guice and other DI frameworks
• Lifecycle Method Annotations (@PrePersist, @PostLoad)
• Built on top of Mongo Java Driver
• More better than old-style queries by BSON-object

48. 48Joker 2015
Morphia advantages
• Integrated with Spring, Guice and other DI frameworks
• Lifecycle Method Annotations (@PrePersist, @PostLoad)
• Built on top of Mongo Java Driver
• More better than old-style queries by BSON-object
• Query API: ds.createQuery(MyEntity.class)
.filter("foo >",12)
.order("date, -foo");

49. 49Joker 2015
Model
@Entity(“customers")
class Customer {
@Id String taxId;
Date memberSince;
boolean active;
int followers;
List<String> following;
}

50. 50Joker 2015
Model with embedded entity
@Entity(“customers")
class Customer {
@Id String taxId;
Name name;
Date memberSince;
boolean active;
int followers;
List<String> following;
}
@Embedded
class Name {
String first, last;
}

51. 51Joker 2015
Save
Customer customer = new Customer();
customer.taxId = "zaleslaw";
customer.name = new Name("Alexey", "Zinoviev");
customer.memberSince = dateFmt.parse("Aug 12, 2009");
customer.active = true;
customer.followers = 8;
customer.following = Arrays.asList("Boris", "Tor");
ds.save(customer);

52. 52Joker 2015
Read from database
> db.customers.findOne()
{
"_id" : “zaleslaw",
"className" : "demo.Customer",
"name" : {
"first" : "Alexey",
"last" : "Zinoviev"
},
"memberSince" : ISODate("2009-08-12T04:00:00Z"),
"active" : true,
"followers" : 8,
"following" : [
"Boris",
"Tor"
]
}

53. 53Joker 2015
Find by filter
ds.find(Customer.class).
field("since").lessThan(dateFmt.parse("Jan 1, 2010")).
field("followers").greaterThan(0)

54. 54Joker 2015
Polymorphism
public abstract class EmployeeEntity {
protected String name;
}
public class ManagerEntity extends EmployeeEntity {
protected Boolean approveFunds;
}
public class WorkerEntity extends EmployeeEntity {
protected Integer yearsExperience;
}

55. 55Joker 2015
Polymorphism in RDBMs

56. 56Joker 2015
Polymorphism in RDBMs
1. Union table with (many) NULL values

57. 57Joker 2015
Polymorphism in RDBMs
1. Union table with (many) NULL values
2. Concrete instances without common queries

58. 58Joker 2015
Polymorphism in RDBMs
1. Union table with (many) NULL values
2. Concrete instances without common queries
3. Base table joined with all subtables

59. 59Joker 2015
Polymorphism with Morphia
@Entity(value = "employee", noClassnameStored = false)
public abstract class EmployeeEntity {
@Id
protected ObjectId id;
protected String name;
}
public class ManagerEntity extends EmployeeEntity {
protected Boolean approveFunds;
}
public class WorkerEntity extends EmployeeEntity {
protected Integer yearsExperience;
}

60. 60Joker 2015
Meanwhile in Mongo
{
"_id": ObjectId("5461c8bf9e2acf32ed5ab079"),
"className": "entities.ManagerEntity",
"name": “Alex",
"approveFunds": true
}
{
"_id": ObjectId("524d9fe7e4b0f8bd3031f89e"),
"className": "entities.WorkerEntity",
"name": “Max",
"yearsExperience": 100
}

61. 61Joker 2015
SELECTs
public EmployeeEntity findByEmail(final String email) {
return mongoDatastore.find(EmployeeEntity.class)
.field("email").equal(email).get();
}
public List<EmployeeEntity> getAllEmployees() {
return mongoDatastore.find(EmployeeEntity.class).asList();
}
public List<ManagerEntity> getAllManagers() {
return mongoDatastore.find(ManagerEntity.class)
.disableValidation()
.field("className").equal(ManagerEntity.class.getName())
.asList();

62. 62Joker 2015
It’s Time for Java Superhero, yeah!

63. SPRING DATA

64. 64Joker 2015
One faith, one Spring for ages!

65. 65Joker 2015
Spring Data
• Templating : connection configs, collection lifecycle
(create, drop), Map/Reduce + Aggregation
• Mapping: @Document, @Index, @Field
• Repository support: geospatial queries, queries derived
from method signatures (at runtime)
• Paging, sorting, CRUD operations

66. 66Joker 2015
All we need in configs

67. 67Joker 2015
Advanced configs
<mongo:mongo host="${mongo.host}" port="${mongo.port}">
<mongo:options
connections-per-host="${mongo.connectionsPerHost}„
threads-allowed-to-block-for-connection
multiplier="${mongo.threadsAllowedToBlockForConnectionMultiplier}„
connect-timeout="${mongo.connectTimeout}„
max-wait-time="${mongo.maxWaitTime}„
auto-connect-retry="${mongo.autoConnectRetry}„
socket-keep-alive="${mongo.socketKeepAlive}„
socket-timeout="${mongo.socketTimeout}„
slave-ok="${mongo.slaveOk}„
write-number="1„
write-timeout="0„
write-fsync="true"/>
</mongo:mongo>
<mongo:db-factorydbname= "test" mongo-ref="mongo"/>

68. 68Joker 2015
Entity Mapping
@Document
class Customer {
@Id private BigInteger id;
@Indexed private String firstname, lastname;
@Field("email") private String emailAddress;
@DBRef private Set<Customer> contacts;
public Person(String firstname) { … }
@PersistenceConstructor
public Customer(String firstname, String lastname) { … }
…
}

69. 69Joker 2015
Mongo operations
public interface MongoOperations {
// Generic callback-accepting methods
<T> T execute(DbCallback<T> action);
<T> T execute(Class<?> entityClass, CollectionCallback<T> action);
<T> T execute(String collectionName, CollectionCallback<T> action);
}

70. 70Joker 2015
Mongo operations
public interface MongoOperations {
// Generic callback-accepting methods
<T> T execute(DbCallback<T> action);
<T> T execute(Class<?> entityClass, CollectionCallback<T> action);
<T> T execute(String collectionName, CollectionCallback<T> action);
// Higher level access methods
<T> List<T> find(Query query, Class<T> entityClass);
void save(Object objectToSave, String collectionName);
WriteResult updateFirst(Query query, Update update, Class<?>
entityClass);
}

71. 71Joker 2015
Template usage
Mongo mongo = new Mongo();
MongoDbFactory factory = new SimpleMongoDbFactory(mongo, „customers“);
MongoTemplate template = new MongoTemplate(factory);

72. 72Joker 2015
Template usage
Mongo mongo = new Mongo();
MongoDbFactory factory = new SimpleMongoDbFactory(mongo, „customers“);
MongoTemplate template = new MongoTemplate(factory);
Customer me = new Customer (“Alexey", “Zinoviev");
me.setEmailAddress(“Alexey_Zinovyeve@epam.com");
template.save(me);

73. 73Joker 2015
Template usage
Mongo mongo = new Mongo();
MongoDbFactory factory = new SimpleMongoDbFactory(mongo, „customers“);
MongoTemplate template = new MongoTemplate(factory);
Customer me = new Customer (“Alexey", “Zinoviev");
me.setEmailAddress(“Alexey_Zinovyeve@epam.com");
template.save(me);
Query query = new Query(new Criteria("emailAddress")
.is("Alexey_Zinovyeve@epam.com"));
assertThat(template.find(query), is(me));

74. 74Joker 2015
Spring Repositories : it does all job
• Uses a method-naming convention that Spring interprets
during implementation
• Hides complexities of Spring Data templates
• Builds implementation for you based on interface design
• Implementation is built during Spring container load.

75. 75Joker 2015
Typical JPA Repository
public interface PersonRepository extends Repository<Person, BigInteger>
{
// Finder for a single entity
Person findByEmailAddress(String emailAddress);
// Finder for multiple entities
List<Person> findByLastnameLike(String lastname);
// Finder with pagination
Page<Person> findByFirstnameLike(String firstname, Pageable page);
}

76. 76Joker 2015
Mongo Repository
public interface PersonRepository extends Repository<Person, BigInteger>
{
// Finder for a single entity
Person findByEmailAddress(String emailAddress);
// Finder for multiple entities
List<Person> findByLastnameLike(String lastname);
// Finder with pagination
Page<Person> findByFirstnameLike(String firstname, Pageable page);
// Geospatial queries
List<Person> findByLocationNear(Point location, Distance distance);
GeoResults<Person> findByLocationNear(Point location);
}

77. 77Joker 2015
Let’s autowire it!
@Component
public class MyClient {
@Autowired
private PersonRepository repository;
public List<Person> doSomething() {
Point point = new Point(55.7, 70.8);
Distance distance = new Distance(200, Metrics.KILOMETERS);
return repository.findByLocationNear(point, distance);
}
}

78. JONGO

79. 79Joker 2015
Jongo
• Jackson and BSON4Jackson for (Un)marshalling
• No JPA / Hibernate style
• Query in Java as in Mongo Shell

80. 80Joker 2015
Jongo : find
db.users.find( { $or : [ { age : {$gt:20,$lt:30} } ,
{ age : {$gt:50,$lt:60} } ] } )
Iterable<User> users = collection.find ("{ $or : [ { age :
{$gt:20,$lt:30} } , { age : {$gt:50,$lt:60} } ] } ").as(User.class);

81. 81Joker 2015
Java Driver API
DB db = mongo.getDB("users");
DBCollection collection = db.getCollection("users");
DBObject firstQuery = QueryBuilder.start("age").greaterThan(20).lessThan(30).get();
DBObject secondQuery = QueryBuilder.start("age").greaterThan(50).lessThan(60).get();
DBObject query = QueryBuilder.start().or(firstQuery,secondQuery).get();
DBCursor results = collection.find(query);
List<User> users = new ArrayList<User>();
for (DBObject result : results) {
User user = new User();
user.setUsername((String) result.get("username"));
user.setAge((Integer) result.get("age"));
users.add(user);
}

82. 82Joker 2015
Jongo : aggregation
MongoCollection collection = new Jongo(db).getCollection("emails");
collection.aggregate(“ {$project:{sender:1}} ")
.and(“ {$match:{tags:'read'}} ")
.and(“ {$limit:10} ")
.as(Email.class);

83. WHAT ABOUT
HIBERNATE?

84. 84Joker 2015
Hibernate in NoSQL world (by Hibernate opinion)

85. 85Joker 2015
Hibernate in NoSQL world (in reality)

86. 86Joker 2015
Hibernate OGM
• Java Persistence (JPA) support for NoSQL solutions
• JP-QL queries are converted in native backend queries
• Hibernate Search as indexing engine and use full-text
queries
• You can call flush(), commit() and demarcate transactions
• It supports only MongoDB, Neo4j, Infinispan, Ehcache

87. 87Joker 2015
Data cycle

88. 88Joker 2015
OGM mapping
@Entity
@NamedQuery(
name="byItemsQuantity",
query = "SELECT o FROM Order o JOIN o.items i WHERE i.quantity = :quantity"
)
public class Order {
@GeneratedValue(generator = "uuid")
@GenericGenerator(name = "uuid", strategy = "uuid2")
@Id private String id;
private Date date;
@Column(name = "custInfo") private String customerInfo;
@ElementCollection
private List<Item> items;

89. POLYGLOT PERSISTANCE

90. 90Joker 2015
Different databases in one project
• RBDMS: Needs transactional updates and has tabular structure
• Riak: Needs high availability across multiple locations. Can merge
inconsistent writes
• MongoDB: Lots of reads, infrequent writes. Powerful aggregation
mechanism
• Cassandra: Large-scale analytics on large cluster. High volume of
writes on multiple nodes

91. 91Joker 2015
Your application, isn’t it?

92. 92Joker 2015
Kundera
• Atomicity guarantee and Transaction management
• Strictly JPA 2.1 compatible
• It supports Cassandra, Mongo, Hbase, Redis, Neo4j and etc
• @Embedded and @ElementCollection for ColumnFamily and nested
documents
• OneToMany, OneToOne, ManyToMany relationships
• Not full JPQL support for different database

93. 93Joker 2015
Kundera

94. 94Joker 2015
It solves all problems!

95. IN CONCLUSION

96. 96Joker 2015
Other tools
• EclipseLink : different support of different NoSQL
databases
• MJORM : Google Code, XML mapping + MQL (SQL syntax
for Mongo data extracting)
• DataNucleus : support many J as JDO, JPA

97. 97Joker 2015
Abstraction vs Standardization

98. 98Joker 2015
In conclusion
• Think about your data

99. 99Joker 2015
In conclusion
• Think about your data
• Understand you project needs

100. 100Joker 2015
In conclusion
• Think about your data
• Understand you project needs
• Choose right framework

101. 101Joker 2015
In conclusion
• Think about your data
• Understand you project needs
• Choose right framework
• Know & use MongoDB features

102. 102Joker 2015
Listen to your heart … DATA

103. 103Joker 2015
CALL ME
IF YOU WANT TO KNOW MORE
Thanks a lot

104. 104Joker 2015
Contacts
E-mail : Alexey_Zinovyev@epam.com
Twitter : @zaleslaw
LinkedIn: https://www.linkedin.com/in/zaleslaw