Ed presents JSF 2.2 and WebSocket to Gameduell.

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Copyright © 2013, Oracle and/or its affiliates. All rights reserved.

WebSockets
JSF 2.2
HTML5
Edward Burns
@edburns
http://slideshare.net/edburns/
Consulting Member of Staff, Oracle

My plan for your time investment
 HTML5: Why all the fuss?
– What’s in a name?
– Putting it in context
– HTML5 in JSF 2.2

 WebSockets
– What’s in a name
– Under the covers

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Speaker Qualifications – Ed Burns
And non-qualifications
 Involved with JSF since 2002
 Spec lead since 2003
– Most fun part of the job: cleanly integrating other people’s great ideas into

JSF (and hopefully improving on the in the process)
– Not an expert in applying JSF in practice

 Author of four books for McGraw-Hill

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Speaker Qualifications – Ed Burns
Gaming credentials
 Classic Game Fan
 Collection
– Atari 2600 VCS, Intellivision, NES, Sega Master System, TI-99/4A

 Had David Crane autograph my Pitfall! and Pitfall II manuals
 Ran into Warren Robinett at SFO airport

 Maintain fan site for TI-99/4A Game Tunnels of Doom

http://ridingthecrest.com/edburns/classic-gaming/tunnels/

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The following is intended to outline our general product direction. It is intended
for information purposes only, and may not be incorporated into any contract.
It is not a commitment to deliver any material, code, or functionality, and should
not be relied upon in making purchasing decisions. The
development, release, and timing of any features or functionality described for
Oracle’s products remains at the sole discretion of Oracle.

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HTML4
What’s in a name?
 What do people mean when they say HTML4?
– IE6
– Not very high performance JavaScript
– Lots of browser tricks
– Use of native plugins is common

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HTML5
What’s in a name?
 What do people mean when they say HTML5?
– “Modern” browsers
– A gigantic collection of related technologies
 Canvas
 Markup
 Input controls
 Offline storage
 Web components
 EventSource
 Application Cache
 DOM
 WebSocket
 JavaScript
 JSON
 CSS3
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 Geolocation
 XMLHttpRequest Level 2

HTML5
Is it really a big deal?
 The rise of Chrome and the end of polyfill
 Standards have finally won
– How good is your standards body?
 W3C, ECMA, IETF

– HTML5: Microsoft, Google, Apple, what about Mozilla?

 Aside:
– Is HTML5 a bloated specification?

– Is JavaEE a bloated specification?
– What is bloat? A indicator of how old something is.
– http://mir.aculo.us/2010/10/19/standards-bloat-and-html5/
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HTML5
Is it really a big deal?
 The death of the browser plugin: April 2010

http://www.apple.com/hotnews/thoughts-on-flash/
 Where does the tension remain?
– Take advantage of the power in the client
– Minimize the complexity of distributing and maintaining the software

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HTML5
Putting it in context
 HTML5 is a marketing term that describes a way of building the UI for a

distributed system.
– UI processing task resides entirely in the browser

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HTML5
Putting it in context
 For JSF 2.2, HTML5 means just the markup piece
 For JavaEE7 it means WebSocket and JSON

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HTML5 Friendly Markup
The best part of Wicket comes to JSF
 This is a JSF page
<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml"
xmlns:myNS="http://xmlns.jcp.org/jsf”>
<form myNS:id="form">
<input name="textField" type="text" myNS:value="#{bean.text1}" />
<input type="submit" myNS:id="submitButton" value="submit" />
<p>submitted text: #{bean.text1}.</p>
</form>
</html>

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Let’s get back to basics
 JSF Views are written in a View Declaration Language (VDL).
 The standard Facelet VDL is an XML application with two kinds of

elements
– HTML Markup
– JSF Components

 HTML Markup is passed through straight to the browser
 JSF Components take some action on the server, during the lifecycle

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Let the elegance of HTML shine through
 Before JSF 2.2
– JSF tags hide complexity of underlying HTML+script+css+images
– JSF “Renderer”:
 encode: markup to browser
 decode: name=value from browser

<html>…
<my:colorPicker value=“#{colorBean.color2}” />
<my:calendar value=“#{calendarBean.date1}” />
</html>
 Context: Missing feature in browser? Write a JSF component.
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 With JSF 2.2
– Pure HTML+script+css+images in the JSF page
– JSF Renderer handles decode from browser
 Leverage the strength of the JSF lifecycle
 Leverage the expressiveness of HTML5

<html>…
<input type=“color” jsf:value=“#{colorBean.color2}”/>
<input type=“date” jsf:value=“#{calendarBean.date1}” />
</html>
 Context: New feature in browser? Use “pass through elements”
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Pass Through Attributes
 HTML5 users need data-* attributes (and other non-standard

attributes)
 Two styles
– nested attribute
– namespaced attribute

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Pass Through Attributes: nested attribute
<h:outputText value="Simple outputText">
<f:passThroughAttributes value="#{bean.passThroughAttrs}" />

</h:outputText>

 #{bean.passThroughAttrs} is assumed to be a map
 Each entry in the map is output as a name=“value” pair on the

enclosing element.

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<h:outputText value="Simple outputText">
<f:passThroughAttribute name=“data-required”
value=”true" />
</h:outputText>

 Attribute data-required=“true” rendered on markup of enclosing

component.

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Pass Through Attributes: namespaced attribute
<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml"
xmlns:h="http://xmlns.jcp.org/jsf/html"
xmlns:pt="http://xmlns.jcp.org/jsf/passthrough">
<h:form>
<h:inputText id="email" value="#{personPage.selectedPerson.email}"

pt:type="email" pt:placeholder="Enter email">
</h:inputText>
</h:form>
</html>

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 Attributes type=“email” placeholder=“Enter email” rendered on markup

of enclosing component

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 DEMO

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WebSockets

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WebSockets
What’s In a name?
 Several moving parts, each with its own standard!
– Client: W3C JavaScript API http://dev.w3.org/html5/websockets/
– Transport: IETF RFC 6455 http://www.ietf.org/rfc/rfc6455.txt
– Server: JSR-356: http://jcp.org/en/jsr/detail?id=356

 Even with all these parts, it’s still very understandable
– Client: 17 page downs
– Transport: 86 page downs (about a third of which you can skip)
– Server: 43 pages

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WebSockets

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WebSocket
Big Picture
 It really is a Socket for the Web
– It just works over proxies

 Lets you do TCP easily in a web app
– Establish the connection
– Send messages both ways
– Send messages independent of timing
– Close the connection

 Two basic types: text and binary

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WebSocket
Establish the connection

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WebSocket
TCP over HTTP, use the Upgrade: header

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WebSocket

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WebSocket

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WebSocket
Browser Support – caniuse.com

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JavaScript/Browser Client
JavaScript WebSocket Object
 Minimal Lifecycle
– new WebSocket(url)
– pass in some functions
 onopen
 onmessage
– call send()
– call close()

 Can connect to arbitrary servers, other than the page origin
 Server may enforce use of Origin header

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JavaScript WebSocket Object
 [Clamp] if value is

out of
range, truncate it to
closest in-range
value for that
primitive type.

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Examine JavaScript client portion of Roger’s matrix demo
 Traverse connection

lifecycle

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Java Server
Java Endpoint
 Minimal Lifecycle
– Handshake
– Messaging
– Close

 All methods that deal with communication to the other endpoint are

passed a javax.websocket.Session.
 Has nothing to do with javax.servlet.http.HttpSession.
 HttpSession can be obtained from HandshakeRequest
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Java Server
Java Endpoint
 Passing Parameters

 example URI “/bookings/JohnSmith”: guestID is “JohnSmith”
 Strings and primitives supported

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Java Server
Java Endpoint
Two Styles
 Annotated
– The most commonly used

– Very easy to get started
– Throw it in the WAR and you’re done

 Programmatic
– If you don’t want to bake config into your .class files
– Must use Java inheritance

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Java Server
Programmatic Endpoint
 Must bootstrap via ServletContextListener
– Look up the javax.websocket.server.ServerContainer attribute
– It will be an instance of javax.websocket.server.ServerContainer
– Call addEndpoint(), two variants
 takes a class that is the annotated endpoint class
 takes a ServerEndpointConfig instance

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Java Server
Annotated Endpoint

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Java Server
Annotated Endpoint

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Java Server
Programmatic Endpoint
 The ServerEndpointConfig instance
– getEndpointClass() returns
 annotated endpoint
 class that extends javax.websocket.Endpoint
– getPath() returns the path, may contain url-template content

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WebSocket
Flexible Message Processing
 Send or receive text or binary messages
– As complete messages
– As sequence of partial messages

– Using traditional blocking I/O

 Send or receive WebSocket messages as pure Java Objects (kinda

like Serialization)
– Using encode/decode mechanism
– Encoder/decoder for all primitive types built in

 Send and receive messages synchronously or asynchronously

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Questions?

Ed Burns
@edburns

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The preceding is intended to outline our general product direction. It is intended
for information purposes only, and may not be incorporated into any contract.
It is not a commitment to deliver any material, code, or functionality, and should
not be relied upon in making purchasing decisions. The
development, release, and timing of any features or functionality described for
Oracle’s products remains at the sole discretion of Oracle.

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Ed presents JSF 2.2 and WebSocket to Gameduell.

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