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WebSocketsJSF 2.2HTML5Edward Burns@edburns http://slideshare.net/edburns/Consulting Member of Staff, Oracle
Copyright © 2013, Oracle and/or its affiliates. All rights reserved.3
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
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
And non-qualifications
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Speaker Qualifications – Ed Burns
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/
Gaming credentials
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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 do people mean when they say HTML4?– IE6
– Not very high performance JavaScript
– Lots of browser tricks
– Use of native plugins is common
What’s in a name?
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HTML5
What do people mean when they say HTML5?– “Modern” browsers
– A gigantic collection of related technologies Markup Offline storage EventSource DOM JavaScript CSS3
What’s in a name?
Canvas Input controls Web components Application Cache WebSocket JSON
Geolocation XMLHttpRequest Level 2
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HTML5
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/
Is it really a big deal?
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HTML5
The death of the browser plugin: April 2010http://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
Is it really a big deal?
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HTML5
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
Putting it in context
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HTML5
For JSF 2.2, HTML5 means just the markup piece For JavaEE7 it means WebSocket and JSON
Putting it in context
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HTML5 Friendly Markup
This is a JSF page
The best part of Wicket comes to JSF
<!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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HTML5 Friendly Markup
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
Let’s get back to basics
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HTML5 Friendly Markup
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.
Let the elegance of HTML shine through
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HTML5 Friendly Markup
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”
Let the elegance of HTML shine through
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HTML5 Friendly Markup
HTML5 users need data-* attributes (and other non-standard attributes)
Two styles– nested attribute
– namespaced attribute
Pass Through Attributes
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HTML5 Friendly Markup
<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.
Pass Through Attributes: nested attribute
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HTML5 Friendly Markup
<h:outputText value="Simple outputText">
<f:passThroughAttribute name=“data-required” value=”true" />
</h:outputText>
Attribute data-required=“true” rendered on markup of enclosing component.
Pass Through Attributes: nested attribute
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HTML5 Friendly Markup
<!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>
Pass Through Attributes: namespaced attribute
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HTML5 Friendly Markup
Attributes type=“email” placeholder=“Enter email” rendered on markup of enclosing component
Pass Through Attributes: nested attribute
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HTML5 Friendly Markup
DEMO
Let the elegance of HTML shine through
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WebSockets
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WebSockets
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
What’s In a name?
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WebSockets
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WebSocket
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
Big Picture
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WebSocketEstablish the connection
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WebSocketTCP over HTTP, use the Upgrade: header
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WebSocketTCP over HTTP, use the Upgrade: header
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WebSocketTCP over HTTP, use the Upgrade: header
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WebSocketBrowser Support – caniuse.com
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JavaScript/Browser Client
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
JavaScript WebSocket Object
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JavaScript/Browser ClientJavaScript WebSocket Object
[Clamp] if value is out of range, truncate it to closest in-range value for that primitive type.
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JavaScript/Browser Client
Traverse connection lifecycle
Examine JavaScript client portion of Roger’s matrix demo
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Java Server
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
Java Endpoint
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Java Server
Passing Parameters
example URI “/bookings/JohnSmith”: guestID is “JohnSmith” Strings and primitives supported
Java Endpoint
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Java Server
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
Java Endpoint
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Java Server
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
Programmatic Endpoint
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Java ServerAnnotated Endpoint
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Java ServerAnnotated Endpoint
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Java Server
The ServerEndpointConfig instance– getEndpointClass() returns
annotated endpoint class that extends javax.websocket.Endpoint
– getPath() returns the path, may contain url-template content
Programmatic Endpoint
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WebSocket
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
Flexible Message Processing
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Questions?
Ed Burns@edburns
Copyright © 2013, Oracle and/or its affiliates. All rights reserved.44
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.
Copyright © 2013, Oracle and/or its affiliates. All rights reserved.45