Java%20Server%20Faces

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Java Server Faces
95-733 Internet Technologies

• Model/View/Controller Design Pattern for Web
  Development

Slides adapted from Core JavaServer Faces by
Geary and Horstmann, the J2EE Tutorial from Sun
Microsystems, and Developing a Visual Web JSF
Application from NetBeans.org.
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Three Main Parts to JSF Framework

• A Collection of GUI components for drag and drop
  web site development
• An event driven programming model
• A component model supporting third party
  component development

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Detailed Features of JSF

• Bean management
• Validation model
• Component library that permits extensions
• Flexible rendering (not necessarily XHTML)
• Configurable navigation
• State management
• Conversion Model
• Relies on JSP and Servlet technology
• Think GUI Building for the web

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JSF Fundamentals

• Tags correspond to components in a component tree
• A request normally goes through several stages of
  processing on the server
• A built-in FacesServlet handles request
  processing and the JSF life cycle

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JSF Life Cycle Overview (From the J2EE Tutorial)
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Restore an old or construct a new component page
(or view)
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An old view (component tree) has been retrieved
so allow each component in the view to inspect
data values. These values will be redisplayed if
validation or conversion errors are found.
Adds events to an event queue.
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The submitted values are stored as local
values. If the data is invalid or conversions
are not possible then Render Response is called
directly and the user sees the bad data.
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Local values are OK and are used to update
the beans.
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The action method associated with the button or
link that caused the form to be submitted is
executed. The method returns a string for the
navigation handler. The navigation handler uses
the string to determine the next page.
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The selected page is rendered into a markup
language.
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Development Steps

• Build Model from Java Beans
• - Lifetime Configured by developer
• and managed by JSF
• - Request, Session, or Application
• Scope
• - Setters and getters accessed through
• JSF pages
• Use UI Components to build JSF pages
• - Include JSF Tags, Validation and
• Event Listeners
• Define Page Navigation rules in faces.config.xml

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NetBeans JSF Demonstration(0)
The example is from http//testwww.netbeans.or
g/kb/docs/web/helloweb.html01 Goal Display a
form on the browser. When submitted, the
web server will call our application. The
application will execute code in a java bean
associated with the page. The bean will update
page elements. JSF will render the same page
with the changed data and send the page back to
the web browser.
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Netbeans JSF Demonstration(1)
By adding a binding attribute we add setters and
getters to a component.
1. FilegtNew Project 2. Java Web Application 3.
Name the project HelloWeb 4. Visual Web Java
Server Faces 5. In properties for page1, enter a
page title 6. NavigatorgtPage1gtpage1 Right Click
Add Binding Attribute 7. Expand Woodstock Basic
section of palette 8. Drag a label to page enter
Name return 9. Drag a text field to page enter
Enter your name enter 10. In properties of text
field, change textField1 to nameField 11. Right
Click text field Add Binding Attribute 12. In
properties of label component, enter nameField as
for property 13. Drag a button to the page, type
Say hello and enter. 14. Right click button and
choose Add Binding Component. 15. In button
properties, change id from button1 to
helloButton 16. Drag static text component to the
page. 17. In properties static text field, change
id to helloText 18. Right Click static text and
Add Binding Attribute
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Netbeans JSF Demonstration(2)
19. Drag a Message Group to the page. Good for
error reporting. 20. Double Click the button
component. 21. The Java bean for page1 is
visible. 22. Replace body of helloButton_action
with public String helloButton_action()
String name (String)nameField.get
Text() helloText.setText("Hello, "
name "!") return null
23. Click Run Main Project.