Complementary Mobility
Transferring an application Midlet to a mobile device
Table of Contents
Introduction .............................................................................................................................................. 2
Application Transfer Methods .................................................................................................................. 2
Transferring files using a USB cable .......................................................................................................... 3
Transferring an application using Bluetooth ............................................................................................ 5
Transferring an application using Infrared ............................................................................................... 7
Transferring an application using a memory card .................................................................................... 8
3: Transferring an application Midlet to a mobile device
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Complementary Mobility
Transferring an application Midlet to a mobile device
Introduction
The purpose of this document is to explain how to transfer a completed application Midlet to a mobile
device. This article assumes you are using Windows XP as your host PC operating system.
Articles in this series include:
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1: Introduction to Mobile Application Development
2: Beginning application development with MIDP
3: Transferring an application Midlet to a mobile device
4: Building an interactive application Midlet with MIDP
5: Building a multimedia application with MIDP
Application Transfer Methods
For this example a host PC running Microsoft Windows XP and a mobile phone will be used. You should
have previously tested and debugged your application in the emulator, packaged it up and have a
completed .jar application. On certain devices just the .jar file is required but on other devices you may
need to copy the .jad file too. The .jar file is similar to a .zip file and contains a collection of all the files
required to run the application. Sometimes a .jar file can become very large so a .jad file contains a
description of the file contained within the associated .jar file which becomes a much smaller file.
However, a .jad file cannot be used without a .jar file.
An example of the contents of a .jad file is
MIDlet-1: myApp, myApp.png, myApp
MIDlet-Jar-Size: 1387
MIDlet-Jar-URL: myApp.jar
MIDlet-Name: myApp
MIDlet-Vendor: Unknown
MIDlet-Version: 1.0
MicroEdition-Configuration: CLDC-1.0
MicroEdition-Profile: MIDP-1.0
There are a number of ways of transferring a java Midlet .jar including downloading directly from a
website, as an email attachment, and using ftp over a wireless network connection. However, some of
the more common methods which are explained in this document include:
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Direct cable connection, e.g. USB or Serial
Bluetooth
Infrared
Using a memory card, e.g. SD card
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Complementary Mobility
Transferring an application Midlet to a mobile device
Transferring files using a USB cable
One of the more common methods for transferring a .jar file to a
mobile device is to use a data USB cable (or a serial cable), often
provided free with a mobile device. It is often possible to use the
software suite that comes with the mobile device to transfer an
application so it may be worth checking your product documentation
for your mobile device (as applications operate slightly differently
between manufacturers).
However, it can often be as simple as using direct file transfer. Connecting the USB cable that comes
with the device to a USB port on the development computer may bring up a window similar to that
shown in the diagram.
Clicking “Open folder to view files” will bring up a folder list similar to that shown in the following
diagram. The folders work in a similar way to folders on Windows, so folders can be double-clicked and
folders can contain files and other folders.
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Complementary Mobility
Transferring an application Midlet to a mobile device
Locate a suitable folder, in this instance we will use Other and copy and paste the completed .jar file.
You can find the location of the .jar file by looking in the toolkit interface window following a successful
build.
In order to install and launch your application on the mobile device using a Sony Ericsson K800i you
would go into the handset menu, then select My Files, locate the folder where the application was
placed then highlight it and selecting Install. Select Save in Applications then Start Now.
In summary
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Locate the .jar file and copy it
Connect the mobile device
Identify a suitable folder and paste the copied file
Navigate the mobile device and install the application
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Complementary Mobility
Transferring an application Midlet to a mobile device
Transferring an application using Bluetooth
Bluetooth is a local area networking technology, designed for
short distances. To transfer a packaged application using
Bluetooth you need to enable Bluetooth on your host PC and
ensure that your mobile device supports Bluetooth. To start you need to establish a connection between
the two devices, on a Sony Ericsson k800i this can be achieved by going into the menu then selecting
Settings. Navigate to the Connectivity section then select Bluetooth. Ensure Bluetooth is turned on and
is visible to the host computer. On the host computer go into My Bluetooth Places and double-click Find
Bluetooth Devices.
Locate your mobile device and double-click on it. A list of available services will appear on the display,
look for OBEX File Transfer and select it.
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Complementary Mobility
Transferring an application Midlet to a mobile device
In the taskbar area of the host PC you may be told that a Bluetooth PIN Code is required, this is for
security. Click on the popup message and enter a suitable PIN code that you can remember.
Your mobile device should ask if you wish to add the host PC to ‘My devices’. Select Yes and enter the
PIN code you set in the previous step. Then select yes to access your items on your mobile device.
You can now navigate your mobile device folders to locate a suitable folder, in this instance we will use
the Other folder under the Phone memory folder and copy and paste the completed .jar file. You can
find the location of the .jar file by looking in the toolkit interface window.
In summary
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Enable Bluetooth on the host PC and the mobile device
Pair the mobile device to the host PC
Select the File Transfer OBEX service on the host PC
Locate the .jar file on the host PC and copy it
Identify a suitable folder on the mobile device and paste the copied file
Navigate the mobile device and install the application
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Complementary Mobility
Transferring an application Midlet to a mobile device
Transferring an application using Infrared
If you have an infrared facility on both your mobile device and host PC then you may be able to
use infrared to transfer files.
To enable infrared on a Sony Ericsson k800i go to the handset menu, then navigate to Settings, then
Connectivity. Highlight the Infrared port option and Select it. Ensure that On is selected (or 10 minutes
to automatically switch off infrared after 10 minutes).
Ensure that Infrared is enabled on your host PC and ensure there is a direct line of sight between the
two devices. When the host PC detects the mobile device using infrared you will see something similar
to that shown below.
Locate then select the application and click Send – you will need to allow the mobile device to accept
the application. Once you have transferred the .jar file you may also need to transfer the .jad file.
Once the application is transferred, you can select to run it from the mobile device.
In summary
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Complementary Mobility
Transferring an application Midlet to a mobile device
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Enable Infrared on the host PC and the mobile device
Ensure line of sight and close proximity of the two infrared points
Click the infrared icon on the host PC
Locate the .jar file on the host PC and select it then click Send
Allow the mobile to accept the application
Run the application from the mobile device
Transferring an application using a memory card
One of the quickest ways to transfer an application from the host PC to the
mobile device is to use a memory card if your mobile device supports it. To
transfer an application using a memory card simply remove the memory card
from your mobile device, place it in a suitable card reader attached to your host
PC. The host PC will bring up a window where you can select to open a window
to view files. Copy and paste the application .jar (and .jad if necessary) to a
suitable folder on the memory card. Remove the memory card from the host
PC and re-install the memory card back into the mobile device.
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