PDA Programming Using J2ME

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PDA Programming Using J2ME

• Presenter???
• Date2003/4/8

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Out line

• Introduction J2ME
• CLDC/MIDP API
• Preparation of programming
• Examples
• HTTP Connection, RMS DB, SOAP, XML
• Instruction of application development
• Step by step

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What is J2ME

• Java platform for small devices
• A subset of Java 2 Standard Edition
• For programming the Plam
• For programming the mobile device (e.g mobile
  phones or WinCE)

CDC (Connected Device Configuration) CLDC
(Connected Limited Device Configuration)
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What is J2ME (cont)
Profiles Layer
Configuration Layer
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Configurations Layer

• A configuration defines the minimum set of
  libraries and VM capabilities
• Devices have similar processing and power and
  memory constraints
• EX CDC (Connected Device Configuration)
• CLDC (Connected Limited Device Configuration)

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Profiles Layer

• A profiles layer is a set of Java Based API that
  extend the J2ME definition
• UI and presentation capabilities are generally
  defined at this layer
• EX CLDC gt MIDP (Mobile Information Device
  Profile)
• CDC gt Personal Profile
• CDC gt Foundation Profile

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CLDC (Connected Limited Device Configuration)

• Addresses
• Java language and virtual machine features
• Core Java Libraries
• Input/Output
• Networking
• Security
• Not Addresses (but in MIDP)
• User Interface functionality
• Event handling
• High-Level application model
• Application life-cycle management

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CLDC API

• io
• InputStream, OutputStream, Reader, Writer
• lang - No floating point support
• util
• Calendar, Date, Hashtable, Random, Stack,
  TimeZone, Vector, Enumeration
• javax.microedition.io
• Connection, Datagram, InputConnection,
  OutputConnection, Connector

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MIDP API

• javax.microedition.midlet
• (application management)
• javax.microedition.lcdui
• High-level development
• Form, TextBox, List, Alert
• Low-level development
• Canvas Game applications will likely make heavy
  use of the
• javax.microedition.rms
• RecordStore
• A record store consists of a collection of
  records which will remain persistent across
  multiple invocations of the MIDlet

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MIDP API Tree
View
Displayable
Form
Text Box
List
Alert
Canvas
Date Field
Text Field
String Item
Command
Image
Ticker
Choice Group
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Third-party API

• XML Parser KXML1.2, KXML2.0, Xparse-J 1.1 ...
• Web Services KSOAP 1.2
• Floating support MathFP 2.06

API must based on CLDC/CDC or MIDP
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Programming the Palm Part 1 Choice
Development Environment

• J2ME CLDC API
• Contains a subset of the standard J2SE classes
• J2ME KJAVA API(J2ME1.0.3)
• GUI components
• Access the Palm database (PDB)
• Access to IR port
• Kawt API(J2ME1.0.3)
• Rich GUI components
• J2ME MIDP API
• Works on the top of CLDC
• Some GUI components

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Programming the Palm Part 2 Choice KVM or
Java Virtual Machine

• Different KVM has different support
• KVM (Support J2ME)
• IBM J9 (Support J2ME and specific devices API
  support)

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Programming the Palm Part 3 Choice
Development Toolkit

• J2ME Wireless Toolkit
• Support Palm
• IBM WebSphere (Device Developer)
• Support Palm, WinCE and other devices
• JBuilder 7,8 MobileSet
• Based on J2ME Wireless Toolkit

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XML Example Using KXML1.2 API
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RMS Example
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HTTP Connection Example
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SOAP Example Using KSOAP API
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Links

• http//cs.mis.nsysu.edu.tw/J2ME/
• http//www.javaworld.com/channel_content/jw-j2me-i
  ndex.shtml