The document discusses how the Java Content Repository (JCR) can be used to model content and applications as a tree of nodes and properties. It provides examples of using JCR to model websites, assets, workflows, and applications. Everything in a JCR-powered system can be modeled as content in a tree, including code, configurations, and more.

1. A JCR view of the world 1
A JCR view of the world
a-jcr-folder
a-subfolder
a-jcr-node
propertyA : Nodes have 0..N properties
anotherProperty : Another value
Everything is content, everything is a tree
Bertrand Delacretaz , Senior Developer, Adobe CQ5 team.
Apache Software Foundation member and (current) director
@bdelacretaz - http://grep.codeconsult.ch
Berlin Buzzwords 2012
Powered by Apache Sling (content and rendering) and deck.js
(presentation)
http://localhost:4502/content/bb12.html 1 juin 2012 14:18:09

2. A JCR view of the world 2
JCR?
Java API for content repositories (JSR 283)
A big tree of nodes and properties.
Rich infrastructure for content-based applications.
http://localhost:4502/content/bb12.html 1 juin 2012 14:18:09

3. A JCR view of the world 3
JCR Explorer
Java API for content repositories (JSR 283)
A big tree of nodes and properties.
Rich infrastructure for content-based applications.
http://localhost:4502/content/bb12.html 1 juin 2012 14:18:09

4. A JCR view of the world 4
A basic website page
my-page
jcr:content
jcr:text : This is the text of the page.
jcr:title : Title of my page
images
image_1.jpg
image_2.jpg
The jcr:content subnode will later act as a container for more
complex content structures.
http://localhost:4502/content/bb12.html 1 juin 2012 14:18:09

5. A JCR view of the world 5
A more realistic page
/content /my-site/my-page
jcr:content
jcr:title : Title of my page
content -blocks
block_1
block_2
images
first-image.jpg
original .jpg
renditions
first-image-212x43.jpg
first-image-512x83.jpg
Uses JCR observation to generate renditions when original image is
uploaded.
The first-image node is a folder, not just a file. A "micro-tree" of
content.
http://localhost:4502/content/bb12.html 1 juin 2012 14:18:09

6. A JCR view of the world 6
A print queue
print-queue -example
incoming
printjob _20120524 _1502
printers
canonMP640
done
printjob _20120524 _1458
Laserjet 5M
rejected
printjob _20120524 _1458
Jobs arrive under "incoming" and move under a printer's node while
they are executed. Remember unix spooling?
The "rejected" folder holds jobs that could not be executed.
http://localhost:4502/content/bb12.html 1 juin 2012 14:18:09

7. A JCR view of the world 7
Defining virtual hosts
/etc/map/http
www_geometrixx _de
sling:internalRedirect : /content /geometrixx /de
sling:match : www.geometrixx .de/$
www_geometrixx _fr
sling:internalRedirect : /content /geometrixx /fr
sling:match : www.geometrixx .fr/$
Obvious, transparent...no explanation needed
http://localhost:4502/content/bb12.html 1 juin 2012 14:18:09

8. A JCR view of the world 8
Adobe CQ5's content structure
content
geometrixx _en
libs
wcm/mobile
config
install
apps
wcm/mobile
install
etc
virtual-hosts
var
compiled-scripts
Looks familiar?
http://localhost:4502/content/bb12.html 1 juin 2012 14:18:09

9. A JCR view of the world 9
Code and configurations
/apps/my-app
install
a-bundle .jar
sling.get.servlet .jar
config
o.a.sling.GET.config
config.dev
o.a.sling.logging .config
Sling's JCR installer detects and installs bundles, configs and other
resources.
Scary? Extremely useful - with access controls of course.
http://localhost:4502/content/bb12.html 1 juin 2012 14:18:09

10. A JCR view of the world 10
A workflow model
/etc/workflow/models/my-model
jcr:description : Please approve ...
jcr:title : Content Approval
states
state_1
preconditions
transitions
state_2
preconditions
transitions
Useful JCR features: versioning, access control, observation, ...
Semi-generic editor is relatively easy to implement.
http://localhost:4502/content/bb12.html 1 juin 2012 14:18:09

11. A JCR view of the world 11
Workflow instances
/var/workflow/instances
year2012
month03
day24
wf_45f23c
modelPath : /etc/models/approve _content
wf_45f23d
day25
wf_6534ef
year2011
Under /var for distinct access control and lifecycle.
Purge old workflows? Delete year2011 folder.
http://localhost:4502/content/bb12.html 1 juin 2012 14:18:09

12. A JCR view of the world 12
Ingesting assets
/var/public/incoming
some_image.jpg
invalid .pdf
/var/assets /to-validate
image-to-check.jpg
/content /assets
year2012
month04
validated _image.jpg
/var/readonly /rejected
other_invalid .pdf
Watch the incoming folder using JCR observation
Validate , accept and route assets based on content, filenames, etc.
Only incoming folder needs to be writable by users.
http://localhost:4502/content/bb12.html 1 juin 2012 14:18:09

13. A JCR view of the world 13
Slingbucks sample: ordering coffee
/content /slingbucks
private
confirmed -orders
order_b45627
order_f32136
public
order_c325421
coffeeType : espresso
cupSize : tall
Access control requirements for the private/public folders is obvious.
Orders move from public to private, as if passed over the counter
(using JCR observation).
http://localhost:4502/content/bb12.html 1 juin 2012 14:18:09

14. A JCR view of the world 14
Slingbucks sample: coffee options
/content /slingbucks
coffee -type
capuccino
espresso
cup-type
small
medium
price_factor : 1.4
name_fr : Moyenne
name_en : Medium
Options are defined in content, updates are dynamically applied.
Access control defines who can modify options.
http://localhost:4502/content/bb12.html 1 juin 2012 14:18:09

15. A JCR view of the world 15
Thanks for your attention - I'm @bdelacretaz
http://localhost:4502/content/bb12.html 1 juin 2012 14:18:09

16. A JCR view of the world 16
http://localhost:4502/content/bb12.html 1 juin 2012 14:18:09