Transcript Phones Programming in Java

Cosc 4730
Phone Programming in Java
An Introduction
Java: Blackberry vs Android
• Blackberry use JavaME with a lot of extensions
• We’ll cover the Blackberry JavaME with extensions
•
less JavaME, more Blackberry JavaME
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If it doesn’t apply to a Blackberry, I won’t cover it.
• Android uses “Java”, except is closer in nature
to JavaME with Google/Android’s own twist.
• Because of this, I’ll teach how to code X for
Android as well as Blackberry
Java ME
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Java Platform, Micro Edition
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An environment for applications
Generally for mobile phones, PDA, TVs, and other
embedded devices.
Like Java Standard Edition (SE), applications
written for ME are portable across many devices.

But use each devices native capabilities
Java ME (2)
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Java For Micro devices
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Micro Device:
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Limited processing Power
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Limited Storage Capacity
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No or Low Bandwidth Network Connection
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Phones, PDAs, TV, Car Navigation systems, ...
Capabilities
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Depends on device, but JavaME can:
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Multimedia
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Connectivity
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HTTP, Network (Sockets, Datagrams), Bluetooth,
Infrared, Serial IO, Wifi and Cell Data Network
Gaming
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audio/video playback/recording
Layers, Canvas, 3D support, Sprites
SMS, MMS, File Management, Database, GPS,
Personal Info Management, Security Services
Terms and Standards
Terms and Standards (2)
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CLDC – Connected Limited Device
Configuration
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Most mobile phones and their like.
Terms and Standards (3)
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CLDC and MIDP (Mobile Information Device
Profile)
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Most mobile devices in the last couple of use this
environment .
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CLDC 1.1 (JSR 139) or CLDC 1.0 (JSR 30)
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MIDP 2.0 (JSR 118) or MIDP 1.0 (JSR 37)
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Note: MIDP 2.0 supports at least CLDC 1.0
Terms and Standards (4)
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Also Java Technology for Wireless Industry
(JTWI) JSR 185. Currently JTWI 1.0
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Includes MIDP 2.0
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CLDC 1.0, but 1.1 may be used instead.
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WMA 1.1 (JSR 120)
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Wireless Messaging API, which provides access to text
messaging capabilities (usually SMS).
Optional MMAP 1.1
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Mobile Media API for rendering and recording media
data.
Terms and Standards (4)

A few more we will run into (not a complete list)
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Bluetooth and OBEX - JSR 82
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Mobile 3D Graphics – JSR 184
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Java API for bluetooth
Mobile 3D graphics API
SVG API – JSR 229
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Scalable 2D Vector Graphics API
Architecture
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Optional Packages
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MMAPI, 3D API...
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Profile
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MIDP, PBP, App
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Configuration
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CLDC, CDC
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JVM
CLDC
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MIDP over CLDC is what most cell phones
use:
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CLDC
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No Floating point support
No Object finalization
No support for JNI or reflection
No thread groups or daemon thread
No application-defined class loaders
Implementation-defined error handling.
Class verification is done differently
MIDP
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MIDP applications are called MIDlets
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APIs for
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Application management and control
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User interface
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Persistent storage
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Networking
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Timers
MIDlets
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In a Nutshell and MIDlets is loaded
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Then Startapp()
→ Active process running
→ PauseApp()
→ DestroyApp()
→ Paused Process
→ StartApp()
→ DestroyApp()
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DestoryApp unloads MIDlets
CDLC Application
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On some devices
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An application can be created, instead of a
MIDlet
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Application has a Main(), like normal Java
applications
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MIDlet don't have main, instead extend the
MIDlet class
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SmartPhones are more likely to have
Applications, instead of just MIDlets.
API references
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Java ME techology API Documentation
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http://java.sun.com/javame/referece/apis.jsp
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Includes CLDC, CDC, and Sun optional
packages
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Note: This sun generic JavaME and some
smartphones have added to JavaME
Jsr118 (MIDP 2.0)
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User Interface Package
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javax.microedition.lcdui: The UI API provides a set of features for implementation of user
interfaces for MIDP applications.
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javax.microedition.lcdui.game: The Game API package provides a series of classes that enable
the development of rich gaming content for wireless devices.
Persistence Package
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Application Lifecycle Package
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javax.microedition.rms: The Mobile Information Device Profile provides a mechanism for MIDlets
to persistently store data and later retrieve it.
javax.microedition.midlet: The MIDlet package defines Mobile Information Device Profile
applications and the interactions between the application and the environment in which the
application runs.
Networking Package
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javax.microedition.io: Classes for the Generic Connection framework.
Jsr118 (MIDP 2.0) (2)
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Audio Package
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javax.microedition.media: The MIDP 2.0 Media API is a directly compatible building block of the
Mobile Media API (JSR-135) specification.
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javax.microedition.media.control: This package defines the specific Control types that can be
used with a Player.
Public Key Package
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javax.microedition.pki: Certificates are used to authenticate information for secure Connections.
Core Packages
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java.io: Provides classes for input and output through data streams.
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java.lang: Provides classes that are fundamental to the Java programming language.
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java.util: Contains the collection classes, and the date and time facilities.
For comparison
• Check the Java docs for jsr118 vs Java v6
• Java6: http://java.sun.com/javase/6/docs/api/
• Jsr118:
http://java.sun.com/javame/reference/apis/jsr118/
• JavaMe is very much a small subset of the java
language you are used to using.
• The language is there, but not everything you may
want to use.
Blackberry and android
• Blackberry's can use MIDlet, just like standard
JavaME phone
– But prefer a different method.
• base class is the application class, but is not a MIDlet.
application is closer in nature to a standard Java program,
then a JavaMe app. There is a Main class!
• uses MainScreen for each screen that the applications is
using.
– Note, you can have many screens.
• Android phones uses it own version of Java with
XML.
– Uses an Activity as base class
• very similar to MIDlet.
Android
•No JavaME Standards or
JSRs apply
•Uses an Activity as base
class, but similar to
MIDlets has OnCreate,
OnStart(), onResume(),
onStop()
•For more information:
•http://developer.android.c
om/guide/basics/what-isandroid.html
Android (2)
• Developer pages have lot of examples and
reference guides
– api reference guide:
http://developer.android.com/reference/android/
app/package-summary.html
– Resources and tutorials (where the helloworld
example came from)
• http://developer.android.com/resources/index.html
Q&A