Release Notes

Sun Java™ Wireless Toolkit for CLDC
Version 2.5.2_01

December 2008


Table of Contents

1. Overview
2. New in this Release
3. System Requirements
4. Installation Instructions
5. Running the Toolkit
6. Daylight Saving Time Changes
7. Known Bugs
8. Frequently Asked Questions

1. Overview

Sun Java Wireless Toolkit Version 2.5.2_01 for CLDC is a Security Update that corrects vulnerabilities that might allow an untrusted application to execute arbitrary code. This can only happen if you obtain a malicious program and run it in an earlier version of the toolkit.

The only change between version 2.5.2_01 and version 2.5.2 is the security update, so references to version 2.5.2 on this page and in the documentation correctly identify the most recent feature release. The version 2.5.2 documentation remains valid.

The Sun Java Wireless Toolkit for CLDC, formerly known as the J2METM Wireless Toolkit, is a set of tools for creating MIDP applications. It consists of three main components:

The Sun Java Wireless Toolkit for CLDC implements impressive capabilities that are exposed through standard APIs. The APIs are defined through the Java Community ProcessTM (JCPTM) program:

This release of the Sun Java Wireless Toolkit includes Nokia's Scalable Network Application Package (SNAP) Mobile API and the SNAP Mobile Sample Application as part of the toolkit's External API feature. SNAP Mobile is a combination of client software and server infrastructure that supports the creation of networked, community-enabled multiplayer games. For more information, consult the SNAP Mobile web site at The Emulation Environment, development resources and support for SNAP Mobile are available from Please see SNAP Mobile Emulation Environment Installation for further information.

For more information on using the Sun Java Wireless Toolkit for CLDC to develop applications, see the User's Guide.

2. New in this Release

The multiuser feature makes it possible for multiple users on the same machine to use a single installation of the wireless toolkit. The installer installs the product, then, for each user account it copies a subset of the installation files from the installation directory to a separate working directory named j2mewtk. The default location of the working directory (workdir ) is typically in one of these locations:

Windows:C:\Documents and Settings\User\j2mewtk\2.5.2 (where User is your account name)
Linux:~/j2mewtk/2.5.2 (where ~ is your home directory)

In general, you will use your working directory for the applications you write and any customizatons you make. Consult the User's Guide for a more detailed explanation of this feature.

3. System Requirements

This section describes the system requirements for running the Sun Java Wireless Toolkit for CLDC.

3.1 Required Software



3.2 Required Hardware

Following are the minimum hardware requirements:

4. Installation Instructions

Ensure you have an appropriate Java SE environment installed, as described previously.

Run the installer executable. Follow the instructions provided by the installer.

4.1 SNAP Mobile Emulation Environment Installation

Please note that the SNAP Mobile Emulation Environment needs to be downloaded, installed, and started to successfully run the SNAP Mobile Sample Application. Follow these steps to download and run the emulation environment:

  1. Go to and log in (or create an account first if necessary).
  2. Select SNAP Mobile SDK from the Tools and SDKs section.
  3. Download the installer and run.
  4. Go to \SNAPMobile\tools\ServerEmulator\.
  5. Under Windows, run the server emulator with the following command:

  6. java -jar sm-emu.jar

This starts the emulation environment listening for connections over HTTP on localhost:8080. Run the SnapMobileSample application. It connects to the Server Emulator on this port. You can now log in using any of the preconfigured test accounts test1, test2, and so on (the password is test), or else create a new account using the Create Account button on the Login screen.

5. Running the Toolkit

The installer creates a new program group, Sun Java Wireless Toolkit 2.5.1 for CLDC. This group contains the following aliases:

6. Daylight Savings Time Changes

The United States has planned a change to its Daylight Savings Time (DST) observance beginning in 2007. The Energy Policy Act of 2005 mandates that DST will start on the second Sunday in March and end on the first Sunday in November. In 2007, the start and stop dates will be March 11 and November 4, respectively. These dates are different from previous DST start and stop dates. In 2006, the dates were the first Sunday in April (April 2, 2006) and the last Sunday in October (October 29, 2006).

This release updates the DST rules in the virtual machine (VM) so that time changes are handled correctly.

For more information, see U.S. Daylight Saving Time Changes in 2007.

7. Known Bugs

This is not an exhaustive list of known bugs. It includes those bugs that developers are most likely to encounter in using the toolkit.

Bug ID Description
6415233 The MMAPI MPEG player implementation is unstable. When running the MMAPI TCK api/javax_microedition/media/Player/* test packages sporadic errors occur. The errors cannot be reliably reproduced.
6511054 Bingo Bluetooth example throws null pointer exeception. Calling the method DiscoveryAgent.searchServices(...) can throw a NullPointerException if the Bluetooth device doesn't offer any services.
6532775 On Linux, holding down a keyboard key does not generate repeat events. The test com.motorola.tck.test.api.javax.microedition.MIDP2.1.interactive.CanvasRepeatEventTest fails for this reason. The test passes if a key on the emulator is held down with the mouse.

8. Frequently Asked Questions

For answers to common questions, see the FAQ.

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