New Data Access 2.0? - springdeveloper.comspringdeveloper.com/downloads/S2G_2011_AMS_SpringData.pdf · 2011. 5. 26. · Spring Framework built-in data access support • Transaction

An Introduction to Spring Data

Thomas RisbergVMware

[email protected]: trisberg

Data Access 2.0?OR

Thursday, May 26, 2011

mailto:[email protected]:[email protected]

A couple of recent trends

• Heavyweight Databases• Heavy handed DBAs• Heavyweight App Servers

• Lightweight NOSQL Databases• Lightweight App Servers• Cloud Deployments


Data Access 1.0

• The relational database has been extremely successful the last 25 years

• It was the Swiss Army knife of data access for many developers and it worked well ...

A brief history of data access during the last quarter century


New demands on data access

• ... until we needed inexpensive horizontal scaling for some large web based applications ...

• ... and we needed to deploy our apps in the cloud ...


NOSQL provides specialized tools

• Big Data/Data Warehousing- Hbase, Hadoop, Cassandra

• Web App Backend Caching/Persistence- Redis, Riak, MongoDB

• Social Networking Features- Neo4j

• Disconnected Data Replication- CouchDB


Welcome to Data Access 2.0


Spring Framework built-in data access support

• Transaction abstractions, Data access exceptions

• JDBC - JdbcTemplate• ORM - Hibernate, JPA support• OXM - Object to XML mapping• Cache support (Spring 3.1)

Data Access 1.0


Spring Data

• Spring Data Redis/Riak• Spring Data Mongo/Couch• Spring Data Graph Neo4j• Spring Data Column• Spring Data Blob• Spring Data JPA Repository• Spring Data JDBC Extensions• Spring Gemfire• Spring Hadoop• Grails iNcOnSeQentiaL


What is Spring Data

• Bring classic Spring value propositions to NOSQL and extend the SQL based support

✓ Productivity✓ Programming model consistency

• Support for a wide range of NOSQL databases


Spring Data Building Blocks

• Low level data access APIs✓ MongoTemplate, RedisTemplate ...

• Object Mapping (Java and GORM)• Cross Store Persistence Programming model• Generic Repository support (Hades)• Productivity support in Roo and Grails


Finding Spring Data

• GitHub: https://github.com/SpringSource

• Web page: http://www.springsource.org/spring-data

• Forum:http://forum.springsource.org/forumdisplay.php?f=80


https://github.com/SpringSourcehttps://github.com/SpringSourcehttp://www.springsource.org/spring-datahttp://www.springsource.org/spring-datahttp://forum.springsource.org/forumdisplay.php?f=80http://forum.springsource.org/forumdisplay.php?f=80

Three databases for today’s talk

• Document database

• Relational database

• Graph database


Three persistence strategies for today’s talk

• Lower-level Template approach• Conventions based persistence --

Repositories (Hades)

• Cross-store persistence using JPA and a NOSQL database


• JSON-style documents: Lists, Maps, Primitive values• Documents organized into collections• Full or partial document updates• GridFS for efficiently storing large files• Index support – secondary and compound• Rich query language for dynamic queries• Map/Reduce• Replication and Auto Sharding


http://www.mongodb.org/


http://www.mongodb.orghttp://www.mongodb.org

• Resource management• Callback methods

‣ doInSomeResource

• Exception translation• Simple Query API

Spring Template Pattern


17

Mongo DBusing MongoTemplate

CODEhttps://github.com/trisberg/spring-data-samples/tree/

master/data-mongo-template


https://github.com/trisberg/spring-data-samples/tree/master/data-mongo-templatehttps://github.com/trisberg/spring-data-samples/tree/master/data-mongo-templatehttps://github.com/trisberg/spring-data-samples/tree/master/data-mongo-templatehttps://github.com/trisberg/spring-data-samples/tree/master/data-mongo-template

• Also known as HSQLDB or Hypersonic SQL• Relational Database• Table oriented data model• SQL used for queries• ... you know the rest ...


• Eliminate boilerplate code• interface-only approach• finder methods

• findByLastName• Specifications for type safe queries• JPA CriteriaBuilder integration • QueryDsl integration

Spring Data Repository Support


• Generates Query classes using Java APT• Code completion in IDE• Domain types and properties can be referenced

safely

• Adopts better to refactoring changes in domain types

Type-safe queries for multiple backends including JPA, SQL and MongoDB in Java.

http://www.querydsl.com/


http://www.querydsl.comhttp://www.querydsl.com

• Repository Support✓ Spring Data JPA ✓ Spring Data Mongo

• Spring Data JDBC Extensions


22

Relational database using JPA Repository

CODEhttps://github.com/SpringSource/spring-data-jpa-examples/

tree/master/spring-data-jpa-showcase


https://github.com/SpringSource/spring-data-jpa-examples/tree/master/spring-data-jpa-showcasehttps://github.com/SpringSource/spring-data-jpa-examples/tree/master/spring-data-jpa-showcasehttps://github.com/SpringSource/spring-data-jpa-examples/tree/master/spring-data-jpa-showcasehttps://github.com/SpringSource/spring-data-jpa-examples/tree/master/spring-data-jpa-showcase

• DB is a collection of graph nodes, relationships• Nodes and relationships have properties• Querying is done via a traversal API• Indexes on node/relationship properties• Written in Java, can be embedded• Transactional (ACID)• Master-Slave replication• Standalone using REST API


Spring Data Graph Neo4j

• Using AspectJ support we are providing a new programming model:

• Use annotations to define POJO entities• Constructor advice automatically handles entity

creation

• Entity field state persisted to graph using aspects• Leverage graph database APIs from POJO model• Annotation-driven indexing of entities for search


Spring Data Graph Neo4j Cross-store

• JPA data and “NOSQL” data can share a data model• Separate the persistence provider by using

annotations– could be the entire Entity– or, some of the fields of an Entity

• We call this cross-store persistence– One transaction manager to coordinate the “NOSQL” store

with the JPA relational database– AspectJ support to manage the “NOSQL” entities and

fields• holds on to changed values in “change sets” until the

transaction commits for non-transactional data stores


A cross-store scenario ...

You have a traditional web app using JPA to persist data to a relational database ...


JPA Data Model

Restaurant@Entitypublic class Restaurant {

@Id @GeneratedValue private Long id; private String name; private String city; private String state; private String zipCode;

UserAccount@Entity@Table(name = "user_account")public class UserAccount { @Id @GeneratedValue private Long id; private String userName; private String firstName; private String lastName; @Temporal(TemporalType.TIMESTAMP) private Date birthDate; @ManyToMany(cascade = CascadeType.ALL) private Set favorites;


Cross-store Data Model

Recommendation

@RelationshipEntitypublic class Recommendation { @StartNode private UserAccount user; @EndNode private Restaurant restaurant; private int stars; private String comment;

Restaurant@Entity@NodeEntity(partial = true)public class Restaurant { @Id @GeneratedValue private Long id; private String name; private String city; private String state; private String zipCode;

UserAccount@Entity@Table(name = "user_account")@NodeEntity(partial = true)public class UserAccount { @Id @GeneratedValue private Long id; private String userName; private String firstName; private String lastName; @Temporal(TemporalType.TIMESTAMP) private Date birthDate; @ManyToMany(cascade = CascadeType.ALL) private Set favorites;

@GraphProperty String nickname; @RelatedTo(type = "friends", elementClass = UserAccount.class) Set friends; @RelatedToVia(type = "recommends", elementClass = Recommendation.class) Iterable recommendations;


29

Cross-store persistence with JPA/Neo4j

CODEhttps://github.com/SpringSource/spring-data-graph-examples/tree/

1.0.0.RELEASE/myrestaurants-social


https://github.com/SpringSource/spring-data-graph-examples/tree/1.0.0.M1/myrestaurants-socialhttps://github.com/SpringSource/spring-data-graph-examples/tree/1.0.0.M1/myrestaurants-socialhttps://github.com/SpringSource/spring-data-graph-examples/tree/1.0.0.M1/myrestaurants-socialhttps://github.com/SpringSource/spring-data-graph-examples/tree/1.0.0.M1/myrestaurants-social

Questions?

http://www.sxc.hu/photo/860327

http://www.sxc.hu/photo/860327http://www.sxc.hu/photo/860327