9. Platforms – Java ME and Osgi

Department of Computer Science Institute for System Architecture, Chair for Computer Networks

Application Development for Mobile and Ubiquitous Computing

9. Platforms – Java ME and OSGi

Dr. Ing. Thomas Springer Technische Universität Dresden Chair of Computer Networks JAVA MICRO EDITION Java Micro Edition - Overview

Creation of Stand-alone applications for resource limited devices • Native programming limits portability and reusability • Java is a widely deployed platform • supports portability and reusability • issues with resource-limited devices for Java SE

Sun divides today the Java-technology into 3 domains: • Java SE (Standard Edition) ⇨ Desktop applications • Java ME (Micro Edition) ⇨ Resource restricted systems • Java EE (Enterprise Edition) ⇨ Server-side solution

Goals of Java ME • Portability of applications for large range of resource-limited devices • same (Java) programming model • Comfortable development of applications for mobile devices

Fast growing distribution of Java Micro Edition • Number of Java ME-enabled mobile phones: o 2002: 31 Mio. o 2003: 88 Mio. o 2008: 592 Mio. (prognosis)

Dr. Thomas Springer Application Development - Lecture 9. Platforms - Java ME and OSGi 3 Application Domains of Java ME

Designed for devices with restrictions concerning processor power, memory, display size and networking capabilities Heterogeneous requirements for Java ME devices • Personal, mobile, networked devices o Mobile phones, PDA`s, Smart phones, pagers o Characteristics:• Simple User Interfaces • Memory capacity: 128 – 512 kb • Wireless network connection (low bandwidth)

• Commonly used, stationary, networked devices o Set-Top-Boxes, video-phones, entertainment and navigation systems… o Characteristics:• More complex user interfaces • Memory capacity: 2 – 16 MB • Broadband network connection over TCP/IP

Dr. Thomas Springer Application Development - Lecture 9. Platforms - Java ME and OSGi 4 Modular Architecture – Java ME Contents

Optional Packets

Profiles

Configurations CVM

KVM … Kilo Virtual Machine, CVM … Compact Virtual Machine Ref: [Schmatz, Java 2 Micro Edition]

Dr. Thomas Springer Application Development - Lecture 9. Platforms - Java ME and OSGi 5 Modular Architecture- Details

CVM/KVM • Kernel of Java ME • CVM for more powerful devices (High-End PDA) • KVM for resource restricted devices (Mobile Phones) o Restrictions compared to JVM (JNI, Class file-Verifier) Configurations • Horizontal classification of Java ME • Smallest common basis of all devices of that category Profiles • Vertical classification of Java ME • Adaptation to special devices (different display sizes) • Application development (MIDlets) Optional packets • Extension by additional functionality (SMS, MMS, Bluetooth) • support for device-specific functionality

Dr. Thomas Springer Application Development - Lecture 9. Platforms - Java ME and OSGi 6 Configurations

Configuration defines • language support of Java • functionality of Virtual Machine (VM) • basic programming libraries o Usually subset of Java SE used o Alternative/additional functionality defined outside Java SE Two configurations • Connected, Limited Device Configuration (CLDC) o for personal, mobile, weakly-connected devices • Connected Device Configuration (CDC) o for shared, stationary, network integrated devices Different versions per configuration • Currently two versions (1.0 and 1.1) for CDC and CLDC

Dr. Thomas Springer Application Development - Lecture 9. Platforms - Java ME and OSGi 7 Configurations - CDC

Connected Device Configuration (CDC) • Currently available in Version 1.1 (JSR-218) • Characteristics o Powerful CPUs (min. 32 Bit) o High memory resource (min. 4 Mbytes) o Good data transmission rates: permanent network connection Profiles are subsets of Java SE 1.4.2 • Foundation Profile 1.1 (JSR – 219) o Extension of CDC by security packets o No graphical user interfaces possible • Personal Basis Profile 1.1 (JSR-217) o Graphical User Interfaces by subset of AWT o Only light-weight components (container, component) oUsageofX-lets - Similar to MIDlets, States: Loaded, Active, Paused, Destroyed - Communication by Inter-Xlet-Communication(IXC) • Personal Profile 1.1 (JSR-216) o Supports almost all components of AWT o including Heavy Weight components (Buttons, Lists) Dr. Thomas Springer Application Development - Lecture 9. Platforms - Java ME and OSGi 8 Configurations - CLDC

Connected Limited Device Configuration (CLDC) • Currently available in Version 1.1 (JSR-139) • Kilo Virtual Machine o goal: 160 – 512 kb memory used o Subset of Java VM features - no floating point arithmetic (no float and double) (available for CLDC 1.1) - no native functions - no user defined class loaders - no introspection (no serialization, no RMI) - no Thread groups and daemon threads - limited Garbage Collector (no finalize(), no weak references (available for CLDC 1.1))

• Characteristics o Less powerful CPUs with 16-32 Bit o Low memory resources: 192-512 k byte o Short battery life time o Low transmission data rates -> no permanent network connection o Minimal operating system for managing hardware

Dr. Thomas Springer Application Development - Lecture 9. Platforms - Java ME and OSGi 9 Profiles of CLDC

Mobile Information Device Profile (MIDP) • Timer (delay of activities) • Network connection by Generic Connection Framework (GCF) • Persistent memory (RMS) o Mini database as record store organized o Data operations (add, change, delete of records) o Record store assigned to applications • Application development o Generation of MIDlet-Suites • Grafical User Interfaces o Lowest Common Denominator User Interface (LCDUI) •Security o Trusted MIDlet Suites (MIDP 2.0)

Dr. Thomas Springer Application Development - Lecture 9. Platforms - Java ME and OSGi 10 CLDC Application Development

Midlets are basic abstraction for application • Lifecycle managed by Application Management Software (AMS) on mobile Device • Deployed as Midlet Suites

Dr. Thomas Springer Application Development - Lecture 9. Platforms - Java ME and OSGi 11 MIDP Applications (2)

MIDlet-Suites are running in a life cycle Installation, application cycle, de-installation Application cycle • MIDlets are in a state: Active, Paused, Destroyed • Paused in case of inactivity (break in case of other activities) • In state Destroyed: used resources are freed in case of ending the application new()

destroyApp()

pauseApp()

startApp()

destroyApp()

Dr. Thomas Springer Application Development - Lecture 9. Platforms - Java ME and OSGi 12 MIDlet – Basic Structure

import javax.microedition.midlet.*; import javax.microedition.lcdui.*;

public class Fligbookingsystem extends MIDlet implements javax.microedition.lcdui.CommandListener {

// Constructor – invocation of method initialize public Flightbookingsystem() { initialize(); } public void startApp() { }

public void pauseApp() { }

public void destroyApp(boolean unconditional) { }

}

Dr. Thomas Springer Application Development - Lecture 9. Platforms - Java ME and OSGi 13 Midlet Descriptions

Manifest • Part of .jar file • Contains information about the application as attribute assignments • Mandatory attributes: o MIDlet-Name, MIDlet-Version, Midlet-URL, o Configuration and Profile requirements • Optional attributes: o MIDlet-Description, MIDlet-Icon

Java Application Descriptors (JAD) • External of .jar file • Delivers information about the application before the installation on the device • Verification if available resources are sufficient, integrity of .jar and trustability of vendor • Contains Attributes of Manifest and • Signature of Midlet Suite, certificates of vendor and certification authorities, Access permissions

Dr. Thomas Springer Application Development - Lecture 9. Platforms - Java ME and OSGi 14 Midlet GUI

No AWT supported in MIDP • Heterogeneous displays - small monochrome screens up to high resolution, high color screens • Lowest Common Denominator (LCDUI) Approach – weakest resources are reference Two variants for implementing graphical user interfaces • High-level API o Elements for abstract form-based UI elements (button, textbox, date field) o abstract UI elements mapped to native elements o High portability o Look-and-Feel depends on implementation - MIDlets can‘t manipulate visualization of UI elements (shape, color, font) - Simple user interactions handled internally – without notifying the MIDlet (e.g. navigation in dialog larger than display) - Abstraction of input devices and method • Low-level API o Basic graphic functions on Canvas addressing pixels (point, line, rectangle) o handling of physical input elements (e.g. phone buttons) o low level events (e.g. button pressed, button released) oUsed for Game-API

Dr. Thomas Springer Application Development - Lecture 9. Platforms - Java ME and OSGi 15 MIDP classes for GUI creation

Dr. Thomas Springer Application Development - Lecture 9. Platforms - Java ME and OSGi 16 LCDUI - Example

Usage of High-Level API Set display to main menu during initialization of MIDlet For each MIDlet one display is assigned

// This method initializes UI of the application. private void initialize() { getDisplay().setCurrent(get_mainMenu()); }

// This method should return an instance of the display.

public javax.microedition.lcdui.Display getDisplay () { return javax.microedition.lcdui.Display.getDisplay(this); }

Dr. Thomas Springer Application Development - Lecture 9. Platforms - Java ME and OSGi 17 LCDUI – Example – Screens und Items

public javax.microedition.lcdui.Form createInputForm() {

Item items[]=new Item[5]; items[0] = new javax.microedition.lcdui.Spacer(1000, 1); items[1] = new javax.microedition.lcdui.Spacer(1000, 1); items[2] = new javax.microedition.lcdui.TextField("*Name", null, 120, 0x0); items[3] = new javax.microedition.lcdui.TextField("*Flug", null, 120, 0x0); items[4] = new javax.microedition.lcdui.TextField("*Sitz", null, 120, 0x0);

FlightRequest_Storn_InputForm = new javax.microedition.lcdui.Form("Flug – Stornierung", items);

/* Commands of Formular */ FlightRequest_Storn_InputForm.addCommand(createStornCommand()); FlightRequest_Storn_InputForm.addCommand(createBackCommand()); FlightRequest_Storn_InputForm.setCommandListener(this);

return FlightRequest_Storn_InputForm; }

Dr. Thomas Springer Application Development - Lecture 9. Platforms - Java ME and OSGi 18 LCDUI – Example – Create Command

Create Navigation Command /*** Commands ***/

/* Storn */ public javax.microedition.lcdui.Command createStornCommand() {

stornCommand = new javax.microedition.lcdui.Command("Stornierung", javax.microedition.lcdui.Command.OK, 1);

return stornCommand; }

Handle input events public class Fligbookingsystem extends MIDlet implements javax.microedition.lcdui.CommandListener { … // called, if command was performed public void commandAction(javax.microedition.lcdui.Command command, javax.microedition.lcdui.Displayable displayable) { } }

Dr. Thomas Springer Application Development - Lecture 9. Platforms - Java ME and OSGi 19 Midlet network communication

No adoption of “java.net“ due to: • 27 classes in J2SE 1.4 >200 kB (> min. requirement for CLDC) • No consistent usage of protocols (Socket, InetAddress, URLConnection) • Not flexible, because of direct class use, i.e. directly bound to protocol implementation - no interfaces

Generic Connection Framework (GCF) • functional comparable alternative to „java.net“ • Homogenous API for all network types • Contained in “javax.microedition.io“ • Communication Protocols represented by o generic Connection interface implemented by Connector class o Connection provides homogeneous interface for accessing all types of connections o particular connection/protocol implementation is subclass of Connection

Dr. Thomas Springer Application Development - Lecture 9. Platforms - Java ME and OSGi 20 Generic Connection Framework (2)

Mandatory

Dr. Thomas Springer Application Development - Lecture 9. Platforms - Java ME and OSGi 21 Generic Connection Framework (3)

Producing a connecting object through : “Connector.open(String arg)“ arg=scheme:target[;parameters]

Protokolltyp Beispielparameter für arg Interface

HTTP http://java.sun.com HttpConnection HTTPS https://java.sun.com HttpsConnection Sockets (TCP) socket://time-a.nist.gov:13 SocketConnection Serial comm:0;baudrate=2400; CommConnection Datagrams (UDP) datagram://127.0.0.1 UDPDatagramConnection HTTP and HTTPS are suported by all MIDP 2.0 devices, all other types are optional

Dr. Thomas Springer Application Development - Lecture 9. Platforms - Java ME and OSGi 22 Generic Connection Framework (4)

Example: HTTP- Connection

try { HttpConnection con = (HttpConnection)Connector.open("http://www.tu-dresden.de"); } catch (ConnectionNotFoundException ex) { // connection with server can not be established

catch (IOException ex) { // general I/O error } catch (SecurityException ex) { // no rights for network access }

Dr. Thomas Springer Application Development - Lecture 9. Platforms - Java ME and OSGi 23 Midlet data management

For MIDP min. 8kB persistent memory required

Record Management System (RMS) • Simple mechanism for storing persistent data • Device independent API • Not comparable to data base • Simple data store consisting of a set of non-typed data • Data sets are name, value pairs while name=id, variable size

Dr. Thomas Springer Application Development - Lecture 9. Platforms - Java ME and OSGi 24 RMS – Example

// Create record store if it does not exist RecordStore rs = RecordStore.openRecordStore(REC_STORE, true);

// read record

// Allocate space to hold each record byte[] recData = new byte[50];

// Get data into the byte array rs.getRecord(id, recData, 0);

//write record

// Write data into an internal byte array ByteArrayOutputStream strmBytes = new ByteArrayOutputStream();

// Get stream data into byte array and write record byte[] record = strmBytes.toByteArray(); rs.addRecord(record, 0, record.length);

Dr. Thomas Springer Application Development - Lecture 9. Platforms - Java ME and OSGi 25 MIDP2.0 Security (1)

Concept of Trusted MIDlet-Suites Check trustability of vendor and integrity of .jar • Signature contains checksum signed by vendor • .jad contains certificate of vendor and certificate authorities • Root certificates on mobile device • certificate = public key – signed by certificate authority No guaranty for secure transmissions

Development Environment Mobile Device

signing checksum using checksum MIDlet-Suite vendors private key .JAR

add signature to .JAD descriptor MIDlet-Suite validate signature .JAD

root certificate validate vendors of certificate public key authority Midlet provisioning

Over-the-air Provisioning (OTA) • Initiated by user • Controlled by AMS (Application Management Software) Installation process: •.JAD-Server ⇨ with .jad-file (application descriptor) •.JAR-Server ⇨ with .jar-archive • Notification Server ⇨ Gets feedback about installation success

- Often all 3 roles provided by one server

Dr. Thomas Springer Application Development - Lecture 9. Platforms - Java ME and OSGi 27 OTA User Initiated Provisioning

AMS = Application Management Software, part of Java Runtime on mobile device

Dr. Thomas Springer Application Development - Lecture 9. Platforms - Java ME and OSGi 28 Java ME - Integration

[Ref: java.sun.com]

Dr. Thomas Springer Application Development - Lecture 9. Platforms - Java ME and OSGi 29 Development Tools

Toolkits • Sun Wireless Toolkit 2.3 Beta (WTK) • Carbide (formerly Nokia Developer Suite) • Siemens Mobile Toolkit 3.0 (SMTK) • Motorola iDEN SDK for J2ME (MSDK)

Integrated Developement Environments (IDE) • EclipseME 1.1.0 • Sun NetBeans5.0 Mobility Pack5.0 (NMP) • JBuilder 2005 MobileSet3.0.1

Dr. Thomas Springer Application Development - Lecture 9. Platforms - Java ME and OSGi 30 Java ME Summary

Application Development for mobile devices with Java Several Platforms specified • CDC development similar to Java SE • CLDC development varies significantly

Pro: • Configurable platform • Supports large variety of mobile devices • Java development and portability • Web Service support Contra: • Limited portability cased by large variety of configurations, profiles and optional packets • Lowest common denominator approach limites use of device features

Dr. Thomas Springer Application Development - Lecture 9. Platforms - Java ME and OSGi 31 OSGI OSGi - Overview

OSGi = Open Service Gateway Initiative Founded in 1999 Large consortium, BMW, German Telecom, IBM, Siemens, VW

Definition of a specification of a open, standardized, component-based service platform

Initial Application Domains • home and building automation • telematic platform Increasing number of application areas • application platform for mobile devices • platform for dekstop applications (e.g. Eclipse) • embedded systems, e.g. entertainment systems by Philips

Dr. Thomas Springer Application Development - Lecture 9. Platforms - Java ME and OSGi 33 What is OSGi

Local component plattform based on Java • bundles as components • runtime environment for bundles Applications/Bundles • allows multiple applications running on one Java VM Base Services • sharing of components and resources between applications Service Registry

Additional Features on top of Java Life Cycle Platform • management of bundle-lifecycle at Class Loading runtime o Installation, Start, Stop, Update, Deinstallation of Bundles Java VM • Provision of basic services • Service registry Operating System • Dynamic deployment and binding for bundles • Remote bundle management (Remote Management Architecture) • Packet and version management

Dr. Thomas Springer Application Development - Lecture 9. Platforms - Java ME and OSGi 34 Overview about OSGi Components

OSGi Framework Components in OSGi are called Bundles • interface definition • java classes and further resources Bundle A • bundle description - manifest file {…} Bundle B Unit of composition is service {…} Unit of deployment is bundle

Bundle compiled into JAR • Class files • resources Bundle C •Manifest o describes contents of JAR {…} o deployment information, e.g. import and export of java packages for shared use o Description of dependencies = service, defined by = bundle java interface OSGi – Bundle dependencies

The dependencies of a bundle are: • Package dependencies, • Service dependencies, and bundle • Runtime environment dependencies.

bundle bundle

Dr. Thomas Springer Application Development - Lecture 9. Platforms - Java ME and OSGi 36 OSGi – Package Dependencies

Dependencies are defined through the manifest file Framework • Import-Package: org.osgi.framework org.osgi.framework • Export-Package: org.osgi.service.http de.vpe.firstservice The framework resolves these Bundle A dependencies, statically, before Export org.osgi.service.log starting the bundle. com.ibm.service.log • This is the difference between com.ibm.j9 INSTALLED and RESOLVED states. Import org.osgi.service.http javax.servlet.http

Bundle B Export ericsson.osgi javax.servlet javax.servlet.http org.osgi.service.log Import org.osgi.service.http

Dr. Thomas Springer Application Development - Lecture 9. Platforms - Java ME and OSGi 37 OSGi – Bundle Dependencies

Service Dependencies • The dependencies are expressed by bundle to service. • The dependencies can be declared in the manifest file. • A bundle manages dynamic connections between services. • At any time a bundle may display/remove a service interface or require/release the use of a service interface. • The OSGi specification does not mention if every service must handle the complexity about the dynamic addition or removal of external services.

Run-time Environment Dependencies • The framework commonly publishes events associated with: o Insertion of a new bundle, or o Publication of a new service. • Bundles constantly keep listening to these events. • Can take appropriate actions whenever an event happens.

Dr. Thomas Springer Application Development - Lecture 9. Platforms - Java ME and OSGi 38 Bundle – Lifecycle

Bundle lifecycle managed by OSGi runtime environment Bundles my be installed and updated anytime

Install • Evaluation of manifest file • Checking availability of bundle classes and resources • Persistent saving

Resolve • Resolution of static dependencies to external bundles and java packages Uninstall • Must take place explicitly through the OSGi platform • Removal of all persistently saved parts of the bundle

Dr. Thomas Springer Application Development - Lecture 9. Platforms - Java ME and OSGi 39 Example Bundle

1. Step: Service Interface

package Connector; public interface ConnectorService { public String request(String url,char type,int flnr,int snr,String name, boolean s, boolean sdc,boolean w, boolean wdc); }

Dr. Thomas Springer Application Development - Lecture 9. Platforms - Java ME and OSGi 40 Example Bundle Implementation package Connector; 2. Step: import java.io.IOException; Implementation of Service import Connector.EndToEndClient; Interface in Java public class ConnectorServiceImpl implements ConnectorService{ Class

EndToEndClient client;

public String request(String url, char type,int flnr,int snr,String name,boolean s,boolean sdc,boolean w, boolean wdc) { client = new EndToEndClient(url); String FlightRequest_returnValue=""; try { FlightRequest_returnValue = client.ejb_OfficeServlet_processFlightRequest( type,flnr,snr,name,s,sdc,w,wdc); } catch (IOException e) { e.printStackTrace(); } return(FlightRequest_returnValue); } }

Dr. Thomas Springer Application Development - Lecture 9. Platforms - Java ME and OSGi 41 Example Bundle

Manifest-Version: 1.0 3.Step: Manifest Bundle-Name: Connector Bundle-Activator: Connector.Activator Bundle-SymbolicName: Connector Bundle-ClassPath: /j2me.jar,. Bundle-Version: 1.0 Export-Package: Connector, ConnectorService

exports packets Connector, ConnectorService to be available for other bundles

Dr. Thomas Springer Application Development - Lecture 9. Platforms - Java ME and OSGi 42 Example Bundle

package Connector; import org.osgi.framework.BundleActivator; 4. Step: import org.osgi.framework.BundleContext; Bundle-Activator import org.osgi.framework.Constants; import org.osgi.framework.ServiceRegistration;

public class Activator implements BundleActivator { public static BundleContext bc=null;

public void start(BundleContext bc) throws Exception { System.out.println(bc.getBundle().getHeaders().get(Constants.BUNDLE_NAME)+" starting...");

Activator.bc=bc; ConnectorService connect=new ConnectorServiceImpl(); ServiceRegistration registration=bc.registerService( ConnectorService.class.getName(), connect, new Hashtable()); System.out.println("Service registered: ConnectorService"); }

public void stop(BundleContext bc) throws Exception { System.out.println(bc.getBundle().getHeaders().get( Constants.BUNDLE_NAME)+" stopping..."); Activator.bc=null; } } Dr. Thomas Springer Application Development - Lecture 9. Platforms - Java ME and OSGi 43 OSGi – Assemblage

At a given point in time, an OSGi system looks like the figure below:

Dr. Thomas Springer Application Development - Lecture 9. Platforms - Java ME and OSGi 44 Overview of Service Registry

Dr. Thomas Springer Application Development - Lecture 9. Platforms - Java ME and OSGi 45 Example Bundle – Importing a service

package Client; import org.osgi.framework.BundleActivator; import org.osgi.framework.BundleContext; import org.osgi.util.tracker.ServiceTracker; import org.osgi.util.tracker.ServiceTrackerCustomizer; import Connector.ConnectorService; public class Activator implements BundleActivator {

public static BundleContext bc=null; public ServiceTrackerCustomizer customizer; public ServiceTracker tracker; public FlightBookingClient fbc=null;

public void start(BundleContext bc) throws Exception { Activator.bc=bc; fbc=new FlightBookingClient(); customizer=new MyServiceTrackerCustomizer(bc,fbc); tracker=new ServiceTracker(bc,ConnectorService.class.getName(),customizer); tracker.open(); }

public void stop(BundleContext bc) throws Exception { this.tracker.close(); this.customizer=null; this.tracker=null; Activator.bc=null; }

Dr.} Thomas Springer Application Development - Lecture 9. Platforms - Java ME and OSGi 46 package Client; import org.osgi.framework.BundleContext; import org.osgi.framework.ServiceReference; import org.osgi.util.tracker.ServiceTrackerCustomizer; import Connector.ConnectorService; public class MyServiceTrackerCustomizer implements ServiceTrackerCustomizer{

private BundleContext bc=null; private FlightBookingClient fbc=null;

public MyServiceTrackerCustomizer(BundleContext bc,FlightBookingClient fbc){ this.bc=bc; this.fbc=fbc; If tracked service is } registered bind to public Object addingService (ServiceReference reference) { service ConnectorService connect=(ConnectorService)bc.getService(reference); fbc.handservice(connect); fbc.getSendRequestButton().setEnabled(true); fbc.getResultArea().setText(""); return connect; rebind if tracked } service is modified public void modifiedService (ServiceReference reference, Object service) { ConnectorService connect=(ConnectorService)bc.getService(reference); fbc.handservice(connect); unbind if tracked } service is public void removedService (ServiceReference reference, Object service) { deregistered fbc.getSendRequestButton().setEnabled(false); fbc.getResultArea().setText("Der Service ist zur Zeit nicht verfügbar!"); ConnectorService connect=null; fbc.handservice(connect); } } OSGi Plaform Services

Service registry Lifecycle management

Log Service (message logging) HTTP Service UPnP Service Event Admin Service Monitoring Service Service Tracker XML Parser IO Connector Service (basic comm. Infrastructure)

Dr. Thomas Springer Application Development - Lecture 9. Platforms - Java ME and OSGi 48 OSGi Platforms

Open Source • Equinox (Eclipse's OSGi console) • Apache Felix • Knopflerfish • Oscar Commercial • mbedded Server (Prosyst) • AveLink (Atinav) • Service Management Framework (IBM) Extensions • R-OSGi (ETH Zurich, Swiss) o provides a transparent way to access services on remote OSGi platforms • SFelix (INRIA, France) o secure Version of Felix o supports the publication of signed bundles

Dr. Thomas Springer Application Development - Lecture 9. Platforms - Java ME and OSGi 49 Example Equinox (Eclipse's OSGi console)

Dr. Thomas Springer Application Development - Lecture 9. Platforms - Java ME and OSGi 50 Example Equinox (Eclipse's OSGi console)

Dr. Thomas Springer Application Development - Lecture 9. Platforms - Java ME and OSGi 51 Example Knopflerfish

Dr. Thomas Springer Application Development - Lecture 9. Platforms - Java ME and OSGi 52 OSGi Summary

Local, component-based Platform

Unique features • Multiple applications in one Java Environment • Configurable framework with services as bundles • Dynamic installation, update and discovery of bundles

Application areas • Home automation • Embedded systems • Mobile applications

Dr. Thomas Springer Application Development - Lecture 9. Platforms - Java ME and OSGi 53 References

Java ME • http://java.sun.com/javame/index.jsp • http://today.java.net/pub/a/today/2005/02/09/j2me1.ht ml • http://developers.sun.com/learning/javaoneonline/j1onli ne.jsp?track=4&yr=2007 OSGi • http://www.osgi.org/ • http://wiki.easybeans.org/xwiki/bin/pdf/Main/OSGi • http://www.osgi.org/documents/ • http://www.knopflerfish.org/osgi_service_tutorial.html • http://www.aqute.biz/OSGi/Tutorial • http://felix.apache.org/site/apache-felix-osgi- tutorial.html

Dr. Thomas Springer Application Development - Lecture 9. Platforms - Java ME and OSGi 54