Neo4EMF : Big Models

made possibleAmine BENELALLAM

AtlanMod Research TeamEclipseCon Europe 2013, Ludwigsburgh,

GermanyOctober 31

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Context

Model Management

Model Transformation Model Versionning ….

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Challenges + solutions

Lazy loadingOn demand loadingSave if dirtyEffective Backend

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Database Market

Relational DBsNoSQL DBs

ColumnDocument Key/value Graph

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Graphs & MDD

Natural Representation

Models as attributed directed graphs

High performanceAdvanced graph traversal algorithms

Model Management

Tech

Graphs

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Towards Graph DBs to Persist Models

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Neo4J

Short presentation Basic concepts

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Neo4j : Short Introduction

Neo4j project started in 2007 in SwedenFirst Version (1.0) was released in 2010

More than 10 Versions (active Community)

Current Version 2.0.0-M06 (MileStone)Labelled nodesConstrained DB

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They trust Neo4j

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Neo4j Graph DB concepts

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Neo4j Graph DB concepts

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Neo4j Graph DB concepts

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Neo4j Graph DB concepts

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Neo4EMF

IntegrationFrameworkProcessData-RepresentationWhat’s new in Neo4EMF

ChangelogPartitioningJava Ecore codegen

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Neo4EMF = EMF+Neo4J_embedded

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Framework

Eclipse Modeling Framework

Neo4EMF

Neo4emfUtils NeoJava codeGen ChangeLog

Neo4j

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ProcessEdit/ create Data

Retrieve data

Check changesNotify get / set

Neo4j Resource

Save

to par

titions

Unload partitions

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Data Representation

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Data Representation

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Neo4EMF-Object

A Neo4EMF-Object is simply a : MinimalEObjectImplAdditional metadata (ID)Notifies changes and access Stores an adapter to capture notifications and store them in the changelog

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Save : ChangeLog

Lightweight entry set that casts and records changes notifications

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Load : Partitioning

Two kinds of partitionsFlat partitions (to gather elements of the same type)Tailed partitions (to hold references to other objects)

Partitions might be flexible Static/Dynamic PartitioningFull-Load

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Unload : Access History

The Unloader uses the data access history recorder to unload partitionsUnloading strategies :

LIFO, FIFOLeast recently used Least frequenty used

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NeoJava Codegen

Adapted codegen templates for :Refined on-demand loading Data access notification Costimized AdapterFactory to cast notifications and store them in the changelogSeparated objects and data

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DemonstrationScenario

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Generate Query

Populates

Discovers

Java.ecore

(it can be any other plugin) org.eclipse.emf.ecore

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Still more to come

Concurrent AccessDistributed modelsSynchronized unloading More Ecore utilities

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Questions

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Don’t forget to

Check us out :www.neo4emf.com

Contact us :neo4emf@gmail.com

Fork us at : https://github.com/neo4emf/Neo4EMF