||This article includes a list of references, but its sources remain unclear because it has insufficient inline citations. (April 2009)|
|Original author(s)||Craig McClanahan|
|Developer(s)||Apache Software Foundation|
|Initial release||May 2000|
|Stable release||188.8.131.52 GA / June 3, 2013|
|License||Apache License 2.0|
Apache Struts is an open-source web application framework for developing Java EE web applications. It uses and extends the Java Servlet API to encourage developers to adopt a model–view–controller (MVC) architecture. It was originally created by Craig McClanahan and donated to the Apache Foundation in May, 2000. Formerly located under the Apache Jakarta Project and known as Jakarta Struts, it became a top-level Apache project in 2005.
Design goals and overview
In a standard Java JEE web application, the client will typically call to the server via a web form. The information is then either handed over to a Java Servlet which interacts with a database and produces an HTML-formatted response, or it is given to a JavaServer Pages (JSP) document that intermingles HTML and Java code to achieve the same result. Both approaches are often considered inadequate for large projects because they mix application logic with presentation and make maintenance difficult.
The goal of Struts is to separate the model (application logic that interacts with a database) from the view (HTML pages presented to the client) and the controller (instance that passes information between view and model). Struts provides the controller (a servlet known as
ActionServlet) and facilitates the writing of templates for the view or presentation layer (typically in JSP, but XML/XSLT and Velocity are also supported). The web application programmer is responsible for writing the model code, and for creating a central configuration file
struts-config.xml that binds together model, view, and controller.
Requests from the client are sent to the controller in the form of "Actions" defined in the configuration file; if the controller receives such a request it calls the corresponding Action class that interacts with the application-specific model code. The model code returns an "ActionForward", a string telling the controller what output page to send to the client. Information is passed between model and view in the form of special JavaBeans. A powerful custom tag library allows it to read and write the content of these beans from the presentation layer without the need for any embedded Java code.
Struts is categorized as a request-based web application framework.
Struts also supports internationalization by web forms, and includes a template mechanism called "Tiles" that (for instance) allows the presentation layer to be composed from independent header, footer, menu navigation and content components.
- Simple POJO-based actions
- Simplified testability
- Thread safe
- AJAX support
- Template support
- Support for different result types
- Easy to extend with plugins
- REST plugin (REST-based actions, extension-less URLs)
- Convention plugin (action configuration via Conventions and Annotations)
- Spring plugin (dependency injection)
- Hibernate plugin
- Support in design
- JFreechart plugin (charts)
- jQuery plugin (Ajax support, UI widgets, dynamic table, charts)
- Rome plugin
Competing MVC frameworks
Although Struts is a well-documented, mature, and popular framework for building front ends to Java applications, there are other frameworks categorized as "lightweight" MVC frameworks such as Spring MVC, Stripes, Wicket, Play!, and Tapestry. The new XForms standards and frameworks may also be another option to building complex web form validations with Struts in the future.
The WebWork framework spun off from Apache Struts aiming to offer enhancements and refinements while retaining the same general architecture of the original Struts framework. However, it was announced in December 2005 that Struts would re-merge with WebWork. WebWork 2.2 has been adopted as Apache Struts2, which reached its first full release in February 2007.
In 2004, Sun launched an addition to the Java platform, called JavaServer Faces (JSF). Aside from the original Struts framework, the Apache project previously offered a JSF-based framework called Shale, which was retired in May 2009.
Other MVC frameworks that are JVM-based include Grails.
- James Holmes: Struts: The Complete Reference, McGraw-Hill Osborne Media, ISBN 0-07-223131-9
- Bill Dudney and Jonathan Lehr: Jakarta Pitfalls, Wiley, ISBN 978-0-471-44915-7
- Bill Siggelkow: Jakarta Struts Cookbook, O'Reilly, ISBN 0-596-00771-X
- James Goodwill, Richard Hightower: Professional Jakarta Struts, Wrox Press, ISBN 0-7645-4437-3
- John Carnell and Rob Harrop: Pro Jakarta Struts, Second Edition, Apress, ISBN 1-59059-228-X
- John Carnell, Jeff Linwood and Maciej Zawadzki: Professional Struts Applications: Building Web Sites with Struts, ObjectRelationalBridge, Lucene, and Velocity, Apress, ISBN 1-59059-255-7
- Ted Husted, etc.: Struts in Action, Manning Publications Company, ISBN 1-930110-50-2
- Struts View Assembly and Validation, (PDF format).
- Stephan Wiesner: Learning Jakarta Struts 1.2, Packt Publishing, 2005 ISBN 1-904811-54-X
- Official website
- Struts 2 Plugin Registry
- Struts2 jQuery Plugin
- Struts2 Tutorial
- Struts tutorial on JBoss
- How to Test Struts 2 Actions Without a Container