Getting Started with JXTA for J2ME

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Getting Started with JXTA for J2ME

• Advisor Dr. Ching-Long Yeh
• Report DI.2, ??? (89506005)
• Course XML????

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Abstract

• Ad hoc networks a self-configuring network of
  mobile
• Self-organization ability simplify management,
  robustness, flexible
• Well suited to the vicissitudes of wireless
• P2P model enables mobile devices to assemble
  quickly
• JXTA ("juxtapose") , a set of protocols for P2P
  networking
• In this report
• How the JXTA protocols are extended to MIDP
• How to install and run JXTA demonstration
  programs for MIDP

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Abstract

• JXTA demonstration programs for MIDP
• Chat MIDlet

JXME Proxy (Relay)
DEMO
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Agenda

• Abstract
• JXTA
• Java ME (J2ME)
• JXME
• Summary
• Appendix
• Prerequisite for implementation
• Implementation of J2ME Chat MIDlet
• Implementation of JXME Proxy
• References and Resources

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JXTA

• JXTA defines a set of open protocols for
  peer-to-peer networks
• JXTA (v2.0) Protocol Specification
• XML-based protocols
• Functionalities
• peer discovery
• endpoint routing
• connection binding
• basic query/response message exchange
• network propagation through rendezvous peers

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Java ME

• Java ME
• Java Platform, Micro Edition (Java ME) provides a
  environment for applications running on mobile
  and other embedded devices
• mobile phones, personal digital assistants
  (PDAs), TV set-top boxes, and printers
• MIDP Mobile Information Device Profile (v2.0)
• Implementation Specification
• Subset of Java SE (JDK) ? limited capacity

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Java ME

• MIDP
• javax.microedition.rms
• Record Management System, persistence
• javax.microedition.midlet
• Environment, lifecycle
• javax.microedition.io
• Network
• javax.microedition.lcdui
• UI(User Interface)
• Java.lang. java.util.
• MIDlet application
• javax.microedition.midlet.MIDlet

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Java ME

• MIDlet
• Managed by Application Management software (AMS)
  Paused,Active,destroyed

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JXME

• JXME
• JXTA Java Micro Edition (MIDP/CLDC/CDC) Project
• The goal of the JXME project is to bring JXTA
  functionality to MIDP devices
• A framework
• Why JXME ? ? The constraints of Mobile Device
• XML parser ? memory limits of MIDP devices?
• The state of the network ? needs to be cached ?
  memory limits of MIDP devices?
• MIDP mandates support for HTTP, but socket and
  datagram connections are optional
• JXTA protocols exceed the minimum requirements of
  MIDP ? JXTA relay

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JXME Architecture
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Rendezvous/relays
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Coordination between J2ME Edge Devices and JXTA
Relays

• J2ME peer send HTTP request messages to a JXTA
  relay
• JXTA relay parse each name-value pair in the HTTP
  request? XML messages (JXTA format) ? relay the
  messages over the JXTA network
• JXTA relay receives a message from the JXTA
  network? parse the XML format of the incoming
  message ? author a corresponding HTTP response
• Wait for the J2ME peer to send an HTTP poll
  request ? send the HTTP response back to the J2ME
  peer

1.
2.
Response
3.
4.
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JXME API

• Element elements of JXTA Message
• Message JXTA Message, access methods
• PeerNetwork
• createInstance() create PeerNetwork instance
• connect() connect to relay
• create() peer, group, pipe
• search() peer, group, pipe
• poll() poll the information from relay server
• listen() and close() open and close pipe
• send() send the message to the pipe

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JXME Code Example
Create peer

• Create pipe

Connect to proxy
create pipe
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JXME Code Example

• Find the pipe which we created

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JXME Code Example

• Send message through the pipe which we just find

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JXME Code Example

• Receive message

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Summary

• JXTA furnishes an XML-based, platform-independent
  set of protocols that enable P2P networking
• JXME project brings JXTA functionality into the
  MIDP world
• Vision Ad hoc network ? Every mobile device as
  Server

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Summary

• Not popular ? Why ?
• Cost GPRS, 3G ?
• Mobile device Power consumption, UI ?
• In the future
• WiMax ? cost down
• Wireless ? Leased-line network ? connected
  anytime
• Google Android platform ? ? XMPP protocol
• Trends P2P network XML based protocol

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Appendix
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Prerequisite for implementation

• Required libraries from http//download.java.net/j
  xta/
• jxse-lib-2.5.zip
• JXTA core
• JMEX Proxy libraries
• jxme-2.1.3-bin.zip
• JXME framework
• Chat MIDlet code and libraries
• Tools
• NetBeans (6.0) Mobility pack
• http//www.netbeans.org/

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Implementation of J2ME Chat MIDlet
1. New project ?Mobile ? mobile project from
existing MIDP source
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Implementation of J2ME Chat MIDlet
2. Specify the source and JAD file
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Implementation of J2ME Chat MIDlet
3. Name and Location ? name ? chat
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Implementation of J2ME Chat MIDlet
4. Default Platform Selection use default
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Implementation of J2ME Chat MIDlet
5. Add library chat porject ? right click ?
properties ? add Jar/Zip ? jxta-cldc.jar
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Implementation of J2ME Chat MIDlet
6. Run chat project ? right click ? run project
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Implementation of J2ME Chat MIDlet

• Related files and locations
• Chat source code
• \jxme-2.1.3-bin\midp\demo\chat
• JAD
• \jxme-2.1.3-bin\midp\demo\chat\bin\chat.jad
• Library
• \jxme-2.1.3-bin\midp\demo\chat\lib\jxta-cldc.jar

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Implementation of JXME Proxy
1. New project ? General project ? Java
Application
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Implementation of JXME Proxy
2. name? proxy ? finish
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Implementation of JXME Proxy
3. New Java class ? place the code which we
provide
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Implementation of JXME Proxy

• Code
• package tommy
• import java.io.File
• import net.jxta.platform.NetworkManager
• public class StartJXME_Proxy
• private NetworkManager manager
• public StartJXME_Proxy()
• private void startProxy()
• try
• manager new NetworkManager(NetworkMa
  nager.ConfigMode.PROXY, "ProxyeServer", new
  File(new File(".cache"), "ProxyeServer").toURI())
  
• manager.startNetwork()
• catch (Exception e)
• e.printStackTrace()
• System.exit(-1)
• public static void main(String args)
• StartJXME_Proxy startJXME_proxy new
  StartJXME_Proxy()

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Implementation of JXME Proxy
4. Add libraries ?Libraries ? Add
Jar/folder?\jxse-lib-2.5\.jar
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Implementation of JXME Proxy
5. Run ? project ? right click ? run project
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References and Resources

• Getting Started with JXTA for J2ME,
  http//developers.sun.com/mobility/midp/articles/j
  xme/index.html
• JXTA, https//jxta.dev.java.net/
• JXTA v2.0 Protocol Specification,
  https//jxta-spec.dev.java.net/
• JXTA Community Forum, http//forums.java.net/jive/
  forum.jspa?forumID50start0
• JXTA JXSE Programmers Guide, https//jxta-guide.de
  v.java.net/
• J2ME tutorials, http//developers.sun.com/mobility
  /learning/tutorial/
• Sun Java Wireless Toolkit , http//java.sun.com/pr
  oducts/sjwtoolkit/download.html
• NetBeans, http//www.netbeans.org/

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References and Resources

• Code in Netbeans Project
• ?????share name ? XML-JXME
• Maybe you need to correct the location of
  libraries
• Public JXME proxy
• http//rdv.jxtahosts.net/cgi-bin/relays.cgi?2
• http//192.18.37.369700
• http//192.18.37.379700
• http//192.18.37.389700
• http//192.18.37.399700