jackrabbit-commits mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From conflue...@apache.org
Subject [CONF] Apache Jackrabbit: Jackrabbit Architecture (page edited)
Date Wed, 01 Oct 2008 08:38:00 GMT
Jackrabbit Architecture (JCR) edited by Jukka Zitting
      Page: http://cwiki.apache.org/confluence/display/JCR/Jackrabbit+Architecture
   Changes: http://cwiki.apache.org/confluence/pages/diffpagesbyversion.action?pageId=75329&originalVersion=3&revisedVersion=4

Comment:
---------------------------------------------------------------------

JCR-1774: Jackrabbit concurrency review and invariants

Change summary:
---------------------------------------------------------------------

JCR-1774: Jackrabbit concurrency review and invariants

Change summary:
---------------------------------------------------------------------

JCR-1774: Jackrabbit concurrency review and invariants

Change summary:
---------------------------------------------------------------------

JCR-1774: Jackrabbit concurrency review and invariants

Change summary:
---------------------------------------------------------------------

JCR-1774: Jackrabbit concurrency review and invariants

Content:
---------------------------------------------------------------------

* [How Jackrabbit works]
* [Repository lifecycle]
* [Search implementation]
* [Index readers]
* [Concurrency and locking in Jackrabbit]

The general architecture of Jackrabbit can be described in three Layers: A Content Application
Layer, an API Layer and a Content Repository Implementation Layer.

!overview.png!

h2. Content Applications

Content Applications interact through the JSR-170 API with the Content Repository Implementation.
There are numerous applications that are available for JSR-170 repositories, some of them
are very generic (like a WebDAV server) other applications can be very specific and make use
of the content repository as a store for the information that is used by the applications.
Java Applications can use a JSR-170 content repository as a replacement for anything from
property-files, XML-configuration, certain portions of relational database functionality to
straight file system or blob-management. Using a content repository allows an application
to deal with an arbitrarily large hierarchical space in a scalable manner automatically profiting
from the repository services such as versioning, query, transactions or namespaces which make
a content repository an ideal data store for many applications.

A "Generic Content Application" (an application that has no particular functional focus but
just allows for generic introspection and manipulation of the repository) uses the capabilities
of the node types, access control and other facilities to display a user interface or a network
protocol to the end user, seemingly independent from the content that is stored in the repository.
Examples of such generic applications are "The Content Explorer", "WebDAV Server" or a "Subversion
Server". (Or generic Portal, CMS or DMS applications).

A "Specialized Content Application" operates under the assumption that there are certain node
types that it operates on, and that it is familiar at least partially with the data model
exposed by defined node types. Mostly these node types are defined by the application itself
and ship with the application. These applications use a content repository as their persistence
layer as a natural evolution from the use of an RDBMS or a file system. Examples of "Specialized
Content Applications" have a very wide range from a "DVD Collection Management", to a "Message
Board", to "Workflow and BPM" but also possibly complete next generation "Enterprise Resource
Planning Systems".

h2. Content Repository API

The Content Repository API Layer is split into two major sections.

* The Content Repository API defined by JSR-170
* A number features of a content repository, that have been removed from the JSR-170 specification
since they are difficult to implement on existing non-java-based content repositories and
administrational Repository tasks that have also been deliberately excluded from JSR-170

There are only very few (mostly administrational) applications which make use of the non-JSR-170
APIs provided by Jackrabbit.

The boxes in the architecture chart do not symbolize package names or class names directly
but mostly semantically grouped blocks of functionality.

h2. Content Repository Implementation

The content Repository Implementation portion of the architecture chart reflects the major
building blocks of the jackrabbit content repository implementation.

The size of the blocks symbolizes roughly the amount of code and therefore the complexity
of the individual functional block. Again the functional blocks do not directly map to package
or class names.

There are three scopes in a content repository: A repository scope, a workspace scope and
a session scope.

Every function that is operated against a repository can be attributed to at least one of
these scopes, some functions can operate on more than one scope.

* Repository
* Nodetype
* Version
* NamespaceRegistry
* Workspace
* Query
* Observation
* State
* Xml
* Session
* Path
* HierarchyManager
* QName
* ItemImpl, PropertyImpl, NodeImpl
* ItemId, PropertyId, NodeId
* ItemManager

This is not a complete list but includes some of the most important component of the content
repository implementation.


---------------------------------------------------------------------
CONFLUENCE INFORMATION
This message is automatically generated by Confluence

Unsubscribe or edit your notifications preferences
   http://cwiki.apache.org/confluence/users/viewnotifications.action

If you think it was sent incorrectly contact one of the administrators
   http://cwiki.apache.org/confluence/administrators.action

If you want more information on Confluence, or have a bug to report see
   http://www.atlassian.com/software/confluence



Mime
View raw message