Oracle JDeveloper 10g and JavaServer Faces: High
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Transcript Oracle JDeveloper 10g and JavaServer Faces: High
JDeveloper 10g and
JavaServer Faces:
High-Performance UIs on the Web
Avrom Roy-Faderman
Senior Programmer
May, 2006
Agenda
• A Brief History of Java Web
Apps
• JavaServer Faces
• ADF Faces
• Q&A
A Brief History of Java Web Apps
• Productivity and Maintainability
• Capabilities and Performance
Servlets
• Java classes executed on the
server in response to HTTP
requests
• Originally used to output
HTML
This use required extensive and
awkward Java coding
JSP Model 1
• Files closely resembling
HTML except for:
Some specialized tags
“Scriptlets” – embedded bits of Java
code
• Compiled into Servlets
HTML portions outputted directly into
generated HTML
Specialized tags run bits of Java
Scriptlets run directly
Problems with JSP Model 1
• Hard to Change Page Flow
• Mix of Java (sometimes
extensive Java) and Tags on
Same Page
Model 2 Architectures
• Separate out “View” and
“Controller”
View renders UI
Controller handles page flow and
responds to user requests
• No hardcoded links in view
• Generally no procedural
code in view
A Brief History of Java Web Apps
• Productivity and Maintainability
• Capabilities and Performance
“Thick Client” vs. Web: The Past
Requires
customized client
Large downloads
High-interactivity
High-performance
Runs in unmodified
web browser
Small downloads
Low-interactivity
Low-performance
Server
Server
“Web 2.0”
• Still run in unmodified
browser
• Relatively small download
size
• Much more interactive than
traditional web apps
• Much higher-performance
than traditional web apps
Agenda
• A Brief History of Java Web
Apps
• JavaServer Faces
• ADF Faces
• Q&A
JavaServer Faces
• The J2EE standard Model 2
Web Applicaton Architecture
• Special tag libraries for
JSPs/JSPX documents
Html
Core
• Separate controller
JavaServer Faces
• JSF JSP and Components
• Page Flow
• Managed Beans
Simple JSF JSP Code
<body>
<h:form>
<h:selectOneMenu id="color"
required="true">
<f:selectItem itemLabel="Red"
itemValue="red" />
<f:selectItem itemLabel="Green"
itemValue="green" />
</h:selectOneMenu>
</h:form>
</body>
JSF JSP/JSPX and the Component Palette
JavaServer Faces
• JSF JSP and Components
• Page Flow
• Managed Beans
The JSF Controller: Page Flow
• All page flow information
mainained in faces-config.xml
• JDeveloper has graphical
representations of page flow
JSF Page Flow and the Component Palette
JSF Navigation Cases
• Navigation cases referenced in
JSF JSP/JSPX pages
• Converted into destination by
controller
<h:commandLink action="goHome">
Go home!
</h:commandLink>
JavaServer Faces
• JSF JSP and Components
• Page Flow
• Managed Beans
Managed Beans
• The JSF Controller can be
configured to automatically
create and manage Java objects
• Controller or view can access
“managed properties” on these
objects
• Scoping:
Application
Session
Request
Accessing Managed Properties: JSP
• “JSP Expression Language”
Syntax: #{beanName.propertyName}
Can even have nested properties:
#{beanName.property1.property2}
• Use these expressions as
attributes for tags
<h:outputText
value="#{homeBean.mainLabel} />
Managed Bean Classes
• Each managed bean has a class
that you can edit
Constructor runs at the beginning of the
application/request/session
Methods that allow you to access managed
properties
• Put complex logic in here
instead of putting it in the view
Managed Bean Example
<h:outputText
value="#{homeBean.mainLabel} />
public class NavigationBean {
public NavigationBean() {
if /* some condition */ {
setMainLabel("Red");
} else {
setMainLabel("Green");
}
}
/* … */
}
Conditional Page Flow
• Instead of referring to a JSF
navigation case, refer to a
function that *returns* one.
<h:commandLink
action="#{homeBean.nextAction}">
Go on!
</h:commandLink> public String nextAction() {
if /* some condition */ {
return("goStatus");
} else {
return("goOrder");
}
}
Agenda
• A Brief History of Java Web
Apps
• JavaServer Faces
• ADF Faces
• Q&A
ADF Faces
• Oracle ADF
• The ADF Binding Filter
• Partial Page Refresh
ADF and MVC
• Oracle ADF is a framework
based on MVC architecture
View and Controller
(Desktop Clients)
View (Web and
Wireless Clients)
Controller (Web and
Wireless Clients)
Model
Business Services
ADF and MVC
• Oracle ADF is a framework
based on MVC architecture
ADF Swing
ADF Faces
Components
ADF Binding Filter
ADF Data Bindings
ADF Business Components
ADF Faces
• Oracle ADF
• The ADF Binding Filter
• Partial Page Refresh
ADF Binding Filter
• Runs with each HTTP request
• Sets up a Struts managed bean,
“bindings”, containing all ADF
data bindings
<af:inputText
value="#{bindings.EmpName.inputValue} />
ADF Data
Bindings
Database
Business
Service
The Data Control Palette
ADF Faces
• Oracle ADF
• The ADF Binding Filter
• Partial Page Refresh
Traditional “Web 1.0 Cycle”
Request
submitted
to server
Server
renders
page
Page
downloaded
to user
User clicks
button or link
User fills
out form
Component Trees
• You can think of a JSP/JSPX
document as being a tree of
components
<afh:body>
<af:form>
<af:selectOneMenu id="color"
required="true">
<af:selectItem itemLabel="Red"
itemValue="red" />
<af:selectItem itemLabel="Green"
itemValue="green" />
</af:selectOneMenu>
</af:form>
</afh:body>
Partial Page Refresh
• Use Javascript to submit a form
at times other than when a user
presses a button or link
• On server, re-render only a
portion of component tree
• Download only the appropriate
fragment of HTML
Partial Page Refresh—How It Works
Server
Web Cycle with PPR
Request
submitted
to server
Server
renders
components
User
manipulates
component
Components
downloaded
to user
ADF Faces and PPR
• Many components always use
PPR
Table sorting
Table pagination
Expandable tables and menus
…
• Almost all components can use
PPR
Requires some manual work
Simple PPR Example
<af:inputText id="myTextField"
autoSubmit="true"
partialSubmit="true" />
...
<af:outputText id="myTextOutput"
value="#{homeBean.calculatedVal}"
partialTriggers="myTextField" />
A Few Words about AJAX
Asynchronous
Javascript
And
XML
• PPR is an important part of
“Web 2.0”
But PPR, by itself, isn’t truly asynchronous
ADF Faces (and regular JSF) “supports” full
AJAX, but really only in that it supports
Javascript
Q&A