Apache Wicket

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Apache Wicket

• Java Web Application Framework

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What is Wicket?

• Web Application Framework
• Component-Component-based Framework
• Wicket 1.4 is Java 1.5 compliant

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Where does Wicket fit?
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Request / Response

• JSP Request / Response

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Model 2 (MVC)

• Struts, Spring MVC, Stripes

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Advantages of R/R

• Rendering views is generally quite fast
• Development can leverage existing tag libraries
• Recruiting developers may be easier
• Modern implementations have good support for DI
  and IoC frameworks

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Disadvantages of R/R

• Controller implementations must explicitly
• consider multiple concurrent users and threads
• Controllers generally work literally in terms
  ofHTTP requests and responses
• Controllers often explicitly manage state
• Not strictly Object Oriented
• The programming model is skewed

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The Impedance Mismatch

• The Programming Model
• Programming in Java - do we regularly focus on
  how the JVM manages object instances and
  variables?
• Generally, website development requires an
• understanding of the HTTP protocol.
• IE manually managing state within and across
  requests forces front end handlers to be protocol
  specific.

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What if ... ?

• What if we considered a page ... a Page?
• What if we considered a button ... a Button?
• And upon clicking a button, handled an onClick
  event?
• What if web-development resembled Swing or
  event-driven development?
• What kind of framework could possibly enable
  this?!

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Enter ... Wicket

• Component-based framework
• Instead of creating a controller, servlet or
  action
• class ... create a Page
• Place components on said Page and define how
• each component reacts to user input
• Build the Page in Java to manage HTML page
• elements ... not the other way around

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Web App Config

• web.xml

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Wicket Config

• WicketApplication.java

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General Structure

• Layout the element hierarchy
• Style the elements
• Markup (HTMLs Role)
• Code (Javas Role)
• Properties Files

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Hello World

• Markup
• Java

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Result
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Forms (HTML)

• Markup

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Forms (Java)

• Java

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Component Family
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Advantages

• POJO-centric
• Avoid overuse of XML configuration files
• Fully solve back button problem
• Easy to create bookmarkable pages
• Reusability
• Easy to integrate with Java security
• Compatible with any ordinary HTML editor

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Wicket Resources

• Wicket Links
• http//wicket.apache.org/
• http//wicketstuff.org/
• http//cwiki.apache.org/WICKET/
• Wicket Books
• Wicket in Action (Manning)
• Pro Wicket (Apress)