Content Repository API for Java (JCR) is a specification for a Java platform API for accessing content repositories in a uniform manner. The content repositories are used in content management systems to keep the content data and also the meta-data used in CMS such as versioning meta-data. The specification was developed under the Java Community Process as JSR-170 (Version 1) and as JSR-283 (Version 2). The main Java package is javax.jcr.

A JCR is a type of Object Database tailored to the storage, searching, and retrieval of hierarchical data. The JCR API grew out of the needs of content management systems, which require storage of documents and other binary objects with associated metadata. However the API is applicable to many types of applications. In addition to object storage the JCR provides APIs for versioning of data, transactions, observation of changes in data, and import or export of data to XML in a standard way.

The data in a JCR consists of a tree of Nodes with associated Properties. Data is stored in the Properties, which may hold simple values such as numbers and strings or binary data of arbitrary length. Nodes may optionally have one or more types associated with them which dictate the kinds of properties, number and type of child nodes, and certain behavioral characteristics of the nodes. Nodes may point to other nodes via a special reference type property. In this way nodes in a JCR offer both referential integrity and object oriented concept of inheritance. Additional node types include the referenceable node type which allows the user to reference said node through use of a universally unique identifier. Another popular type is the versionable type. This makes the repository track a document’s history and store copies of each version of the document.

The Content Repository API for Java Technology (JCR) is an ongoing effort to define a standard repository interface for the J2SE/J2EETM platforms. The goal of a content repository API is to abstract the details of application data storage and retrieval such that many different applications can use the same interface, for multiple purposes, without significant performance degradation. Content services can then be layered on top of that abstraction to enable software reuse and reduce application development time.

A traditional application uses multiple data stores during its operation. For example, a typical email application will store its configuration in a property list, its address book in a table, messages within indexed files (folders), message properties in separate tables, and search indices in a binary hash. In most cases, each of those storage formats would have their own interface. The application developer would spend a significant portion of the development effort designing, creating, and maintaining those interfaces.

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Introduction to JSR-170

Module-based CMS

Most tasks in a document’s life-cycle are served by CMS modules. Common modules are document creation/editing, transforming and publishing.

Document transformation language-based CMS

Another approach to CMS building with use of open standards. XSLT-based CMS compile ready documents from XML data and XSLT-template. XML Sapiens-based CMS compile a document from the stream of ‘pure’ data, design template and functionality templates.

Web-based CMS

Another approach to CMS building uses databases such as PostgreSQL, MySQL or MS SQL, and scripting languages or tools such as Coldfusion, PHP, jsp or ASP to interact with the data to parse them into visual content. Data stored in a database is queried and compiled into html pages or other documents and transformed using cascading style sheets. These systems can include a number of other functions, such as discussion boards, blogs, or email newsletters.

A content management system (CMS) is a computer software system used to assist its users in the process of content management. CMS facilitates the organization, control, and publication of a large body of documents and other content, such as images and multimedia resources. A CMS often facilitates the collaborative creation of documents. A web content management system is a content management system with additional features to ease the tasks required to publish web content to web sites.

Web content management systems are often used for storing, controlling, versioning, and publishing industry-specific documentation such as news articles, operators’ manuals, technical manuals, sales guides, and marketing brochures. A content management system may support the following features:

• Import and creation of documents and multimedia material

• Identification of all key users and their content management roles

• The ability to assign roles and responsibilities to different content categories or types.

• Definition of the content workflow tasks, often coupled with event messaging so that content managers are alerted to changes in content.

• The ability to track and manage multiple versions of a single instance of content.

• The ability to publish the content to a repository to support access to the content. Increasingly, the repository is an inherent part of the system, and incorporates enterprise search and retrieval.

• Some content management systems allow the textual aspect of content to be separated to some extent from formatting. For example the CMS may automatically set default colour, fonts, or layout.

Web content management systems

A web content management system is a computer system used to manage and control a large, dynamic collection of web material (HTML documents and their associated images). A CMS facilitates document control, auditing, editing, and timeline management. A Web CMS provides the following key features:

• Automated templates: Create standard visual templates that can be automatically applied to new and existing content, creating one central place to change that look across all content on a site.

• Easily editable content: Once your content is separate from the visual presentation of your site, it usually becomes much easier and quicker to edit and manipulate. Most CMS software include WYSIWYG editing tools allowing non-technical individuals to create and edit content.

• Scalable feature sets: Most CMS have plug-ins or modules that can be easily installed to extend an existing site’s functionality.

• Web standards upgrades: Active CMS solutions usually receive regular updates that include new feature sets and keep the system up to current web standards.

• Workflow management: Workflow is the process of creating cycles of sequential and parallel tasks that must be accomplished in the CMS. For example, a content creator submits a story but it’s not published on the website until the copy editor cleans it up, and the editor-in-chief approves it.

• Document management: CMS solutions always provide a means of managing the life cycle of a document from initial creation time, through revisions, publication, archive, and document destruction.

Web Content Management Systems began to be formally developed as a commercial software product in 1995 by two startups, Sunnyvale, California-based Interwoven and it’s flagship TeamSite product and Austin, Texas-based Vignette’s Vignette Content Management product. As the internet began to grow, likewise, the importance of Web Content Management as a part of IT infrastructure began to grow, other vendors in adjacent markets began to develop their own WCM solutions including Documentum and FileNet who had traditionally built Document Management software. Other WCM providers such as Stellent and Red Dot also began to appear.

A Web content management system (WCMS or Web CMS) is content management system (CMS) software, usually implemented as a Web application, for creating and managing HTML content. It is used to manage and control a large, dynamic collection of Web material (HTML documents and their associated images). A WCMS facilitates content creation, content control, editing, and many essential Web maintenance functions.

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