ColdFusion

This article is about the computer programming language. For other uses, see Cold Fusion (disambiguation).

ColdFusion

Original author(s)	Jeremy and JJ Allaire
Developer(s)	Adobe Systems Incorporated
Initial release	1995
Stable release	Adobe ColdFusion 8.0.1, BlueDragon 7.1
Operating system	Windows, Linux, UNIX, Macintosh
Language	English
Type	Application server
License	Proprietary
Website	ColdFusion Homepage, Railo, BlueDragon

ColdFusion is a commercial, rapid application development platform invented by Jeremy and JJ Allaire. The product made its debut around 1995, leading the way for similar products from Microsoft and another from the open source community named Bluefish. The major difference between ColdFusion and the other WYSIWYG development tools of the time was ColdFusion's ability to interface with a database. This enabled people who would likely have trouble creating a dynamic website to create a dynamic site with remarkable ease.

Overview

One of the distinguishing features of ColdFusion is its associated scripting language, ColdFusion Markup Language (CFML), which compares to the scripting components of ASP, JSP, and PHP in purpose and features, but more closely resembles HTML in syntax. "ColdFusion" is often used synonymously with "CFML", but there are additional CFML application servers besides ColdFusion, and ColdFusion supports programming languages other than CFML, such as server-side Actionscript and embedded scripts that can be written in a JavaScript-like language known as CFScript.

Originally a product of Allaire and released in July 1995, ColdFusion was developed by brothers Joseph JJ and Jeremy Allaire. In 2001 Allaire was acquired by Macromedia, who in turn were acquired by Adobe Systems Inc in 2005.

ColdFusion is most often used for data-driven web sites or intranets, but can also be used to generate remote services such as SOAP web services or Flash remoting. It is especially well-suited as the server-side technology to the client-side Flex.

ColdFusion can also handle asynchronous events such as SMS and instant messaging via its gateway interface, available in ColdFusion MX 7 Enterprise Edition.

Main features

ColdFusion provides a number of additional features out of the box. Among them:

• Simplified database access
• Client and server cache management
• Client-side code generation, especially for form widgets and validation
• Conversion from HTML to PDF and FlashPaper
• Data retrieval from common enterprise systems such as Active Directory, LDAP, SMTP, POP, HTTP, FTP, Microsoft Exchange Server and common data formats such as RSS and Atom
• File indexing and searching service based on Verity K2
• GUI administration
• Server, application, client, session, and request scopes
• XML parsing, querying (XPath), validation and transformation (XSLT)
• Server clustering
• Task scheduling
• Graphing and reporting
• Simplified file manipulation including raster graphics (and CAPTCHA) and zip archives (introduction of video manipulation is planned in a future release)
• Simplified web service implementation (with automated WSDL generation / transparent SOAP handling for both creating and consuming services - as an example, ASP.NET[1] has no native equivalent for <CFINVOKE WEBSERVICE="

http://host/tempconf.cfc?wsdl " METHOD="Celsius2Fahrenheit" TEMP="#tempc#" RETURNVARIABLE="tempf">[2])

Other implementations of CFML offer similar or enhanced functionality, such as running in a .NET environment or image manipulation.

The engine was written in C and featured, among other things, a built-in scripting language (CFScript), plugin modules written in Java, and a syntax very similar to HTML. The equivalent to an HTML element, a ColdFusion tag begins with the letters "CF" followed by a name that is inidicative of what the tag is interpreted to, in HTML. E.g. <cfoutput> to begin the output of variables or other content.

In addition to CFScript and plugins (as described), CFStudio provided a design platform with a WYSIWYG display. In addition to ColdFusion, CFSTudio also supports syntax in other languages popular for backend programming, such as Perl. In addition to making backend functionality easily available to the non-programmer, (version 4.0 and forward in particular) integrated easily with the Apache Web Server and with Internet Information Server.

Other features

The first version of ColdFusion (then called Cold Fusion) was released on July 10, 1995. This first version was written almost entirely by one person, Joseph Allaire. Primitive by modern standards, early versions of ColdFusion did little more than database access.

All versions of ColdFusion prior to 6.0 were written using Microsoft Visual C++. This meant that ColdFusion was largely limited to running on Microsoft Windows, although Allaire did successfully port ColdFusion to Sun Solaris starting with version 3.1.

For reasons that may have been tied to lackluster sales the company was sold to Macromedia, then to Adobe. Earlier versions were not as robust as the versions available from version 4.0 forward.

With the release of ColdFusion MX 6.0, the engine had been re-written in Java and supported its own runtime environment, which was easily replaced through its configuration options with the runtime environment from Sun. Version 6.1 included the ability to code and debug Shockwave Flash.

History

• 1995 : Allaire Cold Fusion version 1.0
  
• 1996 : Allaire Cold Fusion version 1.5
  
• 1996 : Allaire Cold Fusion version 2.0
  
• 1997-Jun : Allaire Cold Fusion version 3.0
  
• 1998-Jan : Allaire Cold Fusion version 3.1
  
• 1998-Nov : Allaire ColdFusion version 4.0 (space eliminated between Cold and Fusion to make it ColdFusion)
  
• 1999-Nov : Allaire ColdFusion version 4.5
  
• 2001-Jun : Macromedia ColdFusion version 5.0
  
• 2002-May : Macromedia ColdFusion MX version 6.0 (build 6,0,0,48097), Updater 1 (build 6,0,0,52311), Updater 2 (build 6,0,0,55693), Updater 3 (build 6,0,0,58500)
  
• 2003-Jul : Macromedia ColdFusion MX version 6.1 (build 6,1,0,63958), Updater 1 (build 6,1,0,83762)
  
• 2005 : Macromedia ColdFusion MX 7 (build 7,0,0,91690), 7.0.1 (build 7,0,1,116466), 7.0.2 (build 7,0,2,142559)
  
• 2007-Jul-30 : Adobe ColdFusion 8 (build 8,0,0,176276)
  
• 2008-Apr-04 : Adobe ColdFusion 8.0.1 (build 8,0,1,195765)

Versions

ColdFusion MX

Prior to 2000, Allaire began a project codenamed "Neo". This project was later revealed as a ColdFusion Server re-written completely using Java. This made portability easier and provided a layer of security on the server, because it ran inside a Java Runtime Environment. Senior software engineer Damon Cooper, still with Adobe, was the major initiator of the Java move.

On January 16, 2001, Allaire announced a pending merger with Macromedia. Macromedia continued its development and released the product under the name ColdFusion 5.0. It retained the name "ColdFusion" through the remainder of version 5 releases. In June 2002 Macromedia released the product under a slightly different name, allowing the product to be associated with the Macromedia brand, as well as the brand that the Allaire brothers had given it, originally: ColdFusion MX (6.0). ColdFusion MX was completely rebuilt from the ground up and was based on the Java 2 Enterprise Edition (J2EE) platform. ColdFusion MX was also designed to integrate well with Macromedia Flash using Flash Remoting.

With the release of ColdFusion MX, the CFML language API was released with an OOP interface.

ColdFusion MX 7

With the release of ColdFusion 7.0 on February 7, 2005, the naming convention was amended, rendering the product name "Macromedia ColdFusion MX 7". CFMX 7 added Flash-based, and XForms-based, web forms and a report builder that output in Adobe PDF as well as FlashPaper, RTF and Excel. The Adobe PDF output is also available as a wrapper to any HTML page, converting that page to a quality printable document. The enterprise edition also added Gateways. These provide interaction with non-HTTP request services such as IM Services, SMS, Directory Watchers, and an asynchronous execution. XML support was boosted in this version to include native schema checking.

ColdFusion MX 7.0.2, codenamed "Mystic" includes advanced features for working with Adobe Flex 2.

Adobe ColdFusion 8

On July 30, 2007, Adobe Systems released ColdFusion 8, dropping "MX" from its name. During beta testing the codename used was "Scorpio" (the eighth sign of the zodiac and the eighth iteration of ColdFusion as a commercial product). More than 14,000 developers worldwide were active in the beta process - many more testers than the 5,000 Adobe Systems originally expected. The ColdFusion development team consisted of developers based in Newton/Boston, Massachusetts and Bangalore, India.

Some of the new features are the CFPDFFORM tag, which enables integration with Adobe Acrobat forms, some image manipulation functions, Microsoft .NET integration, and the CFPRESENTATION tag, which allows the creation of dynamic presentations using Adobe Acrobat Connect, the Web-based collaboration solution formerly known as Macromedia Breeze. In addition, the ColdFusion Administrator for the Enterprise version ships with built-in server monitoring. ColdFusion 8 is available on several operating systems including Linux, Mac OS X and Windows Server 2003.

Other additions to ColdFusion 8 are built-in AJAX widgets, file archive manipulation (CFZIP), Microsoft Exchange server integration (CFEXCHANGE), image manipulation including automatic captcha generation (CFIMAGE), multi-threading, per-application settings, Atom and RSS feeds, reporting enhancements, stronger encryption libraries, array and structure improvements, improved database interaction, extensive performance improvements, PDF manipulation and merging capabilities (CFPDF), interactive debugging, embedded database support with Apache Derby, and a more ECMAScript compliant CFSCRIPT.

For development of ColdFusion applications, several tools are available: primarily Adobe Dreamweaver CS4, Macromedia HomeSite 5.x, CFEclipse, Eclipse and others. "Tag updaters" are available for these applications to update their support for the new ColdFusion 8 features.

Adobe ColdFusion 9

Adobe is currently working on ColdFusion 9 (Codename: Centaur). It is currently in the public beta stage. There is no release date set, but the list of potential new features include :

• Ability to code User Defined Functions (UDFs) and ColdFusion Components (CFC's) entirely in CFScript.
• An explicit "local" scope that does not require local variables to be declared at the top of the function.
• Implicit getters/setters for CFC.
• Implicit constructors via method called "init" or method with same name as CFC.
• New CFFinally tag for Exception handling syntax and CFContinue tag for Control flow.
• Object-relational mapping (ORM) Database integration through Hibernate (Java).
• Server.cfc file with onServerStart and onServerEnd methods.
• Tighter integration with Adobe AIR.
• Integration with SharePoint including the document library.

Adobe ColdFusion Builder

Main article: Adobe ColdFusion Builder

Adobe ColdFusion Builder (codenamed "Bolt") is the name for Adobe’s new Eclipse based development IDE that can be used to build applications for ColdFusion. The codename Bolt is a reference to the original lightning icon for the product from the Allaire days.

Although still in development, some of the intended features for the tool include:

• Object Relational Mapping auto-configuration
• Application Code Generation
• Server management
• Easily extensible through the Eclipse framework
• CFML, HTML, Javascript, and CSS Syntax Highlighting
• Code assist for tags, functions, variables, and components
• Code folding
• Snippet creation and management
• Outline viewing
• RDS Explorer for files and databases
• Line-level Debugging

Adobe is currently targeting the commercial release for some time in 2009.

Features

Rich forms

ColdFusion Server includes a subset of its Macromedia Flex 1.5 technology. Its stated purpose is to allow for rich forms in HTML pages using CFML to generate Flash movies. These Flash forms can be used to implement rich internet applications, but with limited efficiency due to the ActionScript restrictions in place on Flash forms by Macromedia.

Flash forms also provide additional widgets for data input, such as date pickers and data grids.

In previous versions of ColdFusion, some form validation and additional widgets were available using a combination of Java applets and JavaScript. This option persists for those who do not wish to use Flash, however not all features are supported.

An example:

<cfform format="flash" method="post" width="400" height="400">
	<cfinput type="text" name="username" label="Username" required="yes" >
	<cfinput type="password" name="password" label="Password" required="yes" >
	<cfinput type="submit" name="submit" value="Sign In" >
</cfform>

ColdFusion also includes some XForms capability, and the ability to "skin" forms using XSLT.

PDF and FlashPaper generation

ColdFusion can generate PDF or FlashPaper documents using standard HTML (i.e. no additional coding is needed to generate documents for print). CFML authors simply place HTML and CSS within a pair of cfdocument tags and specify the desired format (FlashPaper or PDF). The generated document can then either be saved to disk or sent to the client's browser. ColdFusion 8 has now introduced the cfpdf tag which allows for unprecedented control over PDF documents including PDF forms, and merging of PDFs. These tags however do not use Adobe's PDF engine but a free and open source java library called iText.

ColdFusion Components (Objects)

ColdFusion was originally not an object-oriented programming language, and even today lacks some OO features. ColdFusion falls into the category of OO languages that do not support multiple inheritance (along with Java, Smalltalk etc.). With the MX release (6+), ColdFusion introduced the component language construct which resembles classes in OO languages. Each component may contain any number of properties and methods. One component may also extend another (Inheritance). Components only support single inheritance. With the release of ColdFusion 8, Java-style interfaces are supported. ColdFusion components use the file extension cfc to differentiate them from ColdFusion templates (.cfm).

Remoting

Component methods may be made available as web services with no additional coding and configuration. All that is required is for a method's access to be declared 'remote'. ColdFusion automatically generates a WSDL at the URL for the component thusly: http://path/to/components/Component.cfc?wsdl . Aside from SOAP, the services are offered in Flash Remoting binary format.

Methods which are declared remote may also be invoked via an HTTP GET or POST request. Consider the GET request as shown.

http://path/to/components/Component.cfc?method=search&query=your+query&mode=strict This will invoke the component's search function, passing "your query" and "strict" as arguments.

This type of invocation is well-suited for AJAX-enabled applications. ColdFusion 8 introduced the ability to serialize ColdFusion data structures to JSON for consumption on the client.

The ColdFusion server will automatically generate documentation for a component if you navigate to its URL and insert the appropriate code within the component's declarations. This is an application of component introspection, available to developers of ColdFusion components. Access to a component's documentation requires a password. A developer can view the documentation for all components known to the ColdFusion server by navigating to the ColdFusion URL. This interface resembles the Javadoc HTML documentation for Java classes.

Custom tags

ColdFusion provides several ways to implement custom tags, i.e. those not included in the core ColdFusion language. The traditional and most common way is using CFML. A standard CFML page can be interpreted as a tag, with the tag name corresponding to the file name prefixed with "cf_". For example, the file IMAP.cfm can be used as the tag "cf_imap". Attributes used within the tag are available in the ATTRIBUTES scope of the tag implementation page. CFML pages are accessible in the same directory as the calling page, via a special directory in the ColdFusion web application, or via a CFIMPORT tag in the calling page. The latter method does not necessarily require the "cf_" prefix for the tag name.

A second way is the development of CFX tags using Java or C++. CFX tags are prefixed with "cfx_", for example "cfx_imap". Tags are added to the ColdFusion runtime environment using the ColdFusion administrator, where JAR or DLL files are registered as custom tags.

Finally, ColdFusion supports JSP tag libraries from the JSP 2.0 language specification. JSP tags are included in CFML pages using the CFIMPORT tag.

Alternative server environments

ColdFusion originated as proprietary technology based on Web technology industry standards. However, it is becoming a less closed technology through the availability of competing products. Products include Railo, BlueDragon, IgniteFusion, SmithProject and Coral Web Builder.

The argument can be made that ColdFusion is even less platform-bound than raw J2EE or .NET, simply because ColdFusion will run on top of a .NET app server (New Atlanta), or on top of any servlet container or J2EE application server (JRun, WebSphere, JBoss, Geronimo, Tomcat, Resin Server, Jetty (web server), etc.). In theory, a ColdFusion application could be moved unchanged from a J2EE application server to a .NET application server.

Currently, alternative server platforms generally support ColdFusion MX 6.1 functionality, with minor changes or feature enhancements.

Interactions with other programming languages

ColdFusion and Java

The standard ColdFusion installation allows the deployment of ColdFusion as a WAR file or EAR file for deployment to standalone application servers, such as Macromedia JRun, and IBM WebSphere. ColdFusion can also be deployed to servlet containers such as Apache Tomcat and Mortbay Jetty, but because these platforms do not officially support ColdFusion, they leave many of its features inaccessible.

Because ColdFusion is a Java EE application, ColdFusion code can be mixed with Java classes to create a variety of applications and use existing Java libraries. ColdFusion has access to all underlying Java classes, supports JSP custom tag libraries, and can access JSP functions after retrieving the JSP page context (GetPageContext()).

Prior to ColdFusion 7.0.1, ColdFusion components could only be used by Java or .NET by declaring them as web services. However, beginning in ColdFusion MX 7.0.1, ColdFusion components can now be used directly within Java classes using the CFCProxy class.

Recently, there has been much interest in Java development using alternate languages such as Jython, Groovy and JRuby. ColdFusion was one of the first scripting platforms to allow this style of Java development. There are, however, some limitations to ColdFusion's ability to offer Java scripting:

• ColdFusion MX 6.1 did not support usage of null value method parameters
• Lack of Bean Scripting Framework plugin support
• one cannot extend Java classes in ColdFusion

ColdFusion and .NET

ColdFusion 8 natively supports .NET within the CFML syntax. ColdFusion developers can simply call any .NET assembly without needing to recompile or alter the assemblies in any way. Data types are automatically translated between ColdFusion and .NET (example: .NET DataTable → ColdFusion Query).

A unique feature for a J2EE vendor, ColdFusion 8 offers the ability to access .NET assemblies remotely through proxy (without the use of .NET Remoting). This allows ColdFusion users to leverage .NET without having to be installed on a Windows operating system.

The move to include .NET support in addition to the existing support for Java, CORBA and COM is a continuation of Adobe ColdFusion's agnostic approach to the technology stack. ColdFusion can not only bring together disparate technologies within the enterprise, but can make those technologies available to a number of clients beyond the web browser including, but not limited to, the Flash Player, Adobe Integrated Runtime (AIR), Mobile devices (SMS), Acrobat Reader (PDF) and IM gateways.

Acronyms

The acronym for the ColdFusion Markup Language is CFML. When ColdFusion templates are saved to disk, they are traditionally given the extension .cfm or .cfml. The .cfc extension is used for ColdFusion Components. The original extension was DBM or DBML, which stood for Database Markup Language. When talking about ColdFusion, most users use the acronym CF and this is used for numerous ColdFusion resources such as user groups (CFUGs) and sites.

CFMX is the common abbreviation for ColdFusion versions 6 and 7 (aka ColdFusion MX).

Notes and references

• "Adobe Ships ColdFusion 8". Adobe Systems Incorporated. 2007-07-30. http://www.adobe.com/aboutadobe/pressroom/pressreleases/200707/073007ColdFusion.html. 

See also

• 4GL
• BlueDragon - Proprietary .NET-based CFML Engine and Free Open Source Java-based CFML Engine (Open BlueDragon)
• ColdFusion Markup Language
• Comparison of programming languages
• Railo - Free, Open Source CFML Engine
• SmithProject - Free, Open Source CFML Engine
• CFUnited - annual ColdFusion conference

External links

• Official Railo site
• Open Source Railo site
• Official ColdFusion site
• ColdFusion at the Open Directory Project
• The ColdFusion section of Rosetta Code
• LearnCF - Learn ColdFusion with ColdFusion tutorials. Every tutorial has a working demo, code view and code download.
• ColdFusion technical mailing list
• ColdFusion Resource Center
• ColdFusion Server Monitoring