advanced jcr persistence in the gatein portal framework · advanced jcr persistence in the gatein...

Copyright © 2010. All rights Reserved, eXo Platform SAS

Advanced JCR Persistence in the GateIn Portal Framework

Julien Viet JUDCon 8th of October 2010


Agenda

•  GateIn introduction •  JCR basics with CRaSH •  Chromattic JCR persistence mapper •  Logomattic a JCR demo


GateIn and above

•  GateIn 3.0 released in March 2010 •  GateIn 3.1 released in June 2010 •  eXo Social 1.0 •  eXo WCM 2.0 •  eXo KS 2.0 •  eXo Platform 1.0


Standards, features and technologies

Standards & Features

GateIn Portal

JBoss eXo

Identity integration WSRP

Model Object for

Portal

Gadget Server

Portlet Container

JBoss Identity

eXo JCR / WebDAV

Chromattic (JCR / Object)

JBoss WS

WebUI

JSR 286 Portlet

Java Content

Repository

Remote Portlets

Rich UI Portal / Portlet

Opensocial Gadgets

Portlet Bridge /

Richfaces

Rest / JAX-RS


Major features

•  Aggregation via Portlet and Gadget •  Rich User Interface •  Java Content Repository •  Internationalization / RTL •  Management •  Identity integration (Database, LDAP) •  SSO integration (SSO, CAS, OpenSSO)


Content aggregation

•  Based on standards and specifications – Portlet 2.0/ GateIn Portlet Container – OpenSocial Gadgets / Shindig


Portal development

•  Portlet bridges – JSF (JSR 301) – Struts 1 & Struts 2 – Apache Tapestry – Apache Wicket

•  Portlet frameworks – Spring MVC Portlet – Grails Portlet


Java Content Repository intro

•  A tree of typed items – Organized as a set of Workspace in a

Repository – Item have a path – Node contains items – Property contain data

•  Simple type: String, Long, Double, Calendar, Boolean)

•  Binary streams •  Reference: a reference (UUID) to another node •  Name: a reference (path) to another node


Java Content Repository


Java Content Repository quickly

•  Two kinds of node types – Primary node type – Mixin node type

•  Session based programming model pretty much like JPA

•  Query support (content is indexed) •  State change notification support •  Node versioning


Chromattic


Chromattic project

•  Developed for GateIn persistence •  Hosted on Google Code under LGPL •  Status:

– 1.0 used in GateIn 3.0 and 3.1 – 1.1 scheduled for GateIn 3.2


What’s wrong with? public void print(Node node) throws RepositoryException {if (node.isNodeType(“nt:file”)) { Node content = node.getNode(“jcr:content”); String mimeType = “”; if (content.hasProperty(“mimeType”) mimeType = content.getProperty(“mimeType”).getString(); System.out.println(“File” + node.getName() + “:” + mimeType); } else if (node.isNodeType(“nt:folder)) { System.out.println(“Folder “ + node.getName()); Iterator i = node.getNodes(); while (i.hasNext()) { Node child = (Node)i.next(); print(node); } else { throw new IllegalArgumentException(“print should not be called

with the node type ” + typeName); }}


JCR by nature is not type safe public void print(Node node) throws RepositoryException {if (node.isNodeType(“nt:file”)) { Node content = node.getNode(“jcr:content”); String mimeType = “”; if (content.hasProperty(“mimeType”) mimeType = content.getProperty(“mimeType”).getString(); System.out.println(“File” + node.getName() + “:” + mimeType); } else if (node.isNodeType(“nt:folder)) { System.out.println(“Folder “ + node.getName()); Iterator<?> i = node.getNodes(); while (i.hasNext()) { Node child = (Node)i.next(); print(node); } else { throw new IllegalArgumentException(“print should not be called

with the node type ” + typeName); }}


OO programming provides type safety public void print(File file) { if (file instanceof Document) { String mimeType = file.getContent().getMimeType

(); System.out.println(“File “ + file.getName() + “

“ + mimeType; else { Folder folder = (Folder)file; System.out.println(“Folder “ + folder.getName(); for (File child : folder.getChildren()) print(child); } }


Chromattic

•  Provides a type safe object model for JCR –  Data + code –  Refactoring friendly

•  Enable rapid development of rich models •  Support JCR specific features

– multiple inheritance – mixins

•  Generation of node type definitions from domain model


Class loading

Compiler

Chromattic classes generation based on APT

File.java File_Chromattic.java

File.class File_Chromattic.class

Class<File> Class<File_Chromattic>

APT

<<extends>>


Chromattic concepts

Chroma'c Session

build() Chroma'c Builder

Chroma'c

Chroma'c

classes

Meta Model

Objects

open()

JCR

Node type defs

Java classes


Entity life cycle

Transient Persistent Removed

Chroma'c Session

create()

destroy()

persist()

insert()

•  ChromatticSession provides support for interacting with objects life cycle


Property mapping

•  Java types are mapped to JCR property types – String as JCR String – Integer/int/Long/long as JCR Long – Boolean/boolean as JCR Boolean – Float/float/Double/double as JCR Double – java.util.Date as JCR Calendar – InputStream as JCR Binary

•  Java enum type mapped to JCR String type


Multivalued property mapping

•  A JCR property can be multivalued and are mapped either to native array type and java.util.List java type

@Property int[] getIntArray();

@Property Integer[] getIntegerArray();

@Property List<Integer> getIntegerList();


Node hierarchy mapping @PrimaryType(name=“folder”)public abstract class Folder {

// Returns the files in the folder @OneToMany public abstract Collection<File> getFiles();}


Node hierarchy inheritance mapping

public abstract class Path { @ManyToOne public abstract Folder getFolder(); }

@PrimaryType(name=“file”)public abstract class File extends Path { …}


Node hierarchy inheritance mapping @PrimaryType(name=“folder”)public abstract class Folder extends Path {

@OneToMany public abstract Collection<Path> getChildren();

@OneToMany public abstract Collection<File> getFiles();

@OneToMany public abstract Collection<Folder> getFolders();}


Collection mapping

•  Unordered collection – Collection<Path> getChildren();

•  Ordered collection based on JCR node order – List<Path> getChildren();

•  Associative collection – Map<String, Path> getChildren();


Relationship and life cycle

•  Transient entity becomes persistent when it is involved in a hierarchical relationship with a parent

File file = session.create(File.class);Folder folder = session.findByPath(Folder.class,

“folder);

// Becomes persistentfolder.getFiles().put(“file”, file);

// That would make it also persistentfile.setParent(folder);



•  A persistent entity becomes removed when it terminates its relationship with its parent

Folder folder = session.findByPath(Folder.class, “folder);

File file = folder.getFiles().get(“file);

// The file becomes removedfile.setParent(null)

// That would also remove itfolder.getFiles().remove(“file”);



•  Adding a persistent entity to a collection will either move the entity, rename the entity

Folder folder1 = …Folder folder2 = …File file = folder1.get(“file”);

// Renames the filefolder1.put(“foo”, file)

// Moves the file to a new parentfolder2.put(“foo”, file);


Collection ordering with a list

•  A JCR node can have its children ordered

Folder folder = session.findByPath(Folder.class, “folder”);

List<File> files = folder.getFiles();

// Moves the first file to the last positionFile f = files.get(0);files.add(files.size()-1, f);


Parameter type and generics inheritance public abstract class Container<T> { @OneToMany public abstract Collection<T> getChildren();}

@PrimaryType(name=“folder”)public abstract class Folder extends Container<Path> {}

public abstract class IdentityContainer<I extends IdentityObject> extends Container<I> {

}


Relationship types

•  Four kinds of relationship – Hierarchic: the default one – Reference – Path – Embedded


Reference relationships

•  JCR provides references between nodes providing support for relationships – Reminder: a reference is actually a node property

of type Reference to another node

public abstract class File extends Path { @MappedBy(“target”) @OneToMany(type=RelationshipType.REFERENCE) public abstract Collection<Link> getLinks();}public abstract class Link extends Path { @MappedBy(“target”); @ManyToOne(type=RelationshipType.REFERENCE) public abstract File getTarget();}


Path relationship

•  Similar to reference based relationship with the differences – No integrity applies (weak reference)

•  A node can point with an invalid path •  The identity of the related node is not garanteed


Embedded relationships

•  Provides a one-to-one relationship to a Java object that models a part of the node type – A mixin type – A super type

•  The relationship occurs between two java objects exposing a different type of the same node


Mixin types // Voterable is a java type that maps a java class to a// JCR mixin type

@MixinType(name=“voteable”)public abstract class Voteable {

public abstract int getVoteCount(); public abstract void setVoteCount(int value);

public void vote() { setVoteCount(getVoteCount() + 1); }}


Embedding a mixin type @PrimaryType(name=“page”)public abstract class Page {

// Returns null if the mixin is not present @OneToOne(type=RelationshipType.EMBEDDED) public abstract Voteable getVoteable();

// Controls the life cycle of the mixin public abstract void setVoteable(Voteable voteable);}


Embedding a super type

•  The use case is to replace inheritance by delegation

•  Similar to the mixin type mapping except it exposes one the super type of the primary node type

•  Provides support for multiple node type inheritance

•  Main difference is that it is not possible to act on the life cycle (for obvious reasons)


Embedding a super type @PrimaryType(name=“describable)public abstract class Describable { @Property(name=“description”); public abstract String getDescription(); public abstract void setDescription(String desc);}

@PrimaryType(name=“page”)public abstract class Page extends Describable { @Owner @OneToOne(type=RelationshipType.EMBEDDED); Describable getDescribable(); // There is not setter!}


Interacting with Chromattic session

•  Find node by – Id – Path – Query


Node attributes annotations public class Foo { // Returns the node id @Id public abstract String getId();

// Returns the node name @Name public abstract String getName();

// Returns the path @Path public abstract String getPath();

// Returns the workspace name @WorkspaceName public abstract String getWorkspaceName();}


Eventing

•  The session provides eventing for state changes –  Entity life cycle changes –  State changes (properties)

•  Enables dependency injection integration

public class InjectingListener implements LifeCycleListener {

public created(Object o) { if (o instanceof FrameworkObject) { ((FrameworkObject)o).setFramework(framework); } }

…}


Chromattic 1.1

•  Groovy integration •  @Inject integration •  Improved property type support

– byte[], Calendar – pluggable property type provider


Roadmap

•  Detached/attached entities •  Type safe query builder •  Bean validation integration •  Object versioning


GateIn Frameworks

•  Chromattic and CRaSH are powerful tools for building applications on top of GateIn

•  http://www.gatein.org •  http://chromattic .googlecode.com •  http://crsh.googlecode.com

advanced jcr persistence in the gatein portal framework · advanced jcr persistence in the gatein...

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