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Guests: Ariel Levin, Jonathan Knudsen, and Cori Kaylor MDR-EdO: Welcome to today's Java Live chat on the Java 2 Platform, Micro Edition (J2ME) Wireless Toolkit 2.2. As many of you know, the J2ME Wireless Toolkit has become the de facto standard toolkit for developing J2ME wireless applications. Version 2.2, which is currently available as a Beta release, adds significant new features to an already award-winning Toolkit. Our guests today are the lead engineer for the Toolkit, Ariel Levin; writer Jonathan Knudsen, who's written a lot about the Toolkit, and product marketing manager Cori Kaylor. They're here to answer your questions about the J2ME Wireless Toolkit 2.2. But first let's get a rundown from our guests on what's new and cool in Version 2.2 of the Toolkit. Ariel, Jonathan, and Cori, what would you say are the most significant new features in version 2.2 of the Toolkit? Jonathan Knudsen: There's an article here that describes the new features. Ariel Levin: The best thing about this new release is the support for a whole set of new APIs: JSR 75 - PIM and FC support; JSR 82 - Bluetooth APIs; JSR 184 - 3D APIs; and last but not least JSR 205 - WMA 2.0. cellman: Can you say a bit about the Toolkit's support for MMS? Can I actually transmit and receive images and audio through the toolkit? Ariel Levin: You can send and receive MMS messages between the emulators. We also have a framework in which you can write Java 2 platform, Standard Edition (J2SE) code to hook into and then connect to the "real" world. Check out the docs for more info. rwmarejka: Do you require Bluetooth hardware to use the APIs or can the hardware be simulated by the WTK? Jonathan Knudsen: The toolkit uses a simulated Bluetooth environment, so no Bluetooth hardware is required. Different instances of the emulator can discover each other and exchange data, and you can even see the data in the network monitor, but it's a simulated environment, much like the simulated messaging environment. Kooorrg: Hi, I did not try the new version, but I have a bone to pick with the previous ones. The memory monitor is not very good. For example, when I'm browsing a List, each keystroke allocates some memory. When I hit the GC button, the memory monitor goes back to the 'baseline'. So basically I have to hit the GC button quite often in order to make the difference between memory allocated internally (by the WTK) and memory allocated by my program. Another problem: the implementation classes should not show up in the allocation tree. How are you addressing those problems? Ariel Levin: The new release will enable you to hide the system classes. As for the GC issue, you can run in a mode which does GC all the time (although it will be very slow). rwmarejka: What platforms will be supported in the final release? Jonathan Knudsen: The final 2.2 release will be for Windows XP and Linux. pRaizada: Do you have a new emulator that supports Mobile Media API? I am looking for something similar to the Series 60 emulator from Nokia. Something that would allow me to capture images using the Ariel Levin: The WTK supports MMAPI. There's no camera emulation, if that's what you're looking for. You can, however, do snapshots from videos. umesh: What type environment is provided by J2ME for 3D graphics? Jonathan Knudsen: The J2ME Wireless Toolkit 2.2 supports JSR 184, the Mobile 3D Graphics API for J2ME. tellman: I hear a lot of developers complaining about how slow Ariel Levin: If you're referring to the WTK, then we had a small bug in 2.0 that slowed down the performance. This was fixed in WTK 2.1. If you're referring to a specific implementation, then you need to turn to the folks that did the actual implementation ... ;-) JAYBUILDER: Can you speak briefly about the security features of this new version compared to those of the previous versions? Ariel Levin: We've enhanced the security tools in the 2.2 beta release and a bit more for the upcoming final release to make them fit real life scenarios. This includes: generating a CSR, importing cert chains and key pairs, and putting the cert chain into the JAD when signing a MIDlet suite. jimmy: How can J2ME be used in Bluetooth technologies? Jonathan Knudsen: The J2ME Wireless Toolkit supports JSR 82, the Java APIs for Bluetooth. cellman: When should we expect to see mobile devices that implement 3D graphics (JSR 184)? Cori Kaylor: Actually, 3D devices are already available in the market. Sony Ericsson and Motorola have some on the market. rwmarejka: Are the command line interfaces still supported for integration with Ant? Ariel Levin: All the command line interfaces that were there in previous versions of the WTK are still there. umesh: What kind of technologies are provided by J2ME? Jonathan Knudsen: To understand J2ME at a high level, try this article. tellman: Why was the JSP 184 binary scene format (M3G) created from the ground up, as opposed to using some other established file format? Some manufactures (SE, Motorola) use Mascot Capsule formats which I guess have some benefits as opposed to M3G. Plus, there is practically no widely available converter/tools to export 3D scenes into M3G. Wouldn't this threaten acceptance of this format by developers? Ariel Levin: This is a question that would better be directed at the 184 expert group. My guess is that they wanted something that was not proprietary to a certain company/manufacturer (but this is just a guess). rama_1234: Why should I start using 2.2 instead of 2.1.3? Cori Kaylor: WTK 2.2 supports more advanced devices so you could write cool applications that utilize Bluetooth or PDA functionality. Falken: The screen flickers a lot when I invoke Ariel Levin: Are you using full screen mode? If so, this could be due to a bug in the 2.2 beta version. Falken: Yes I am using full screen mode. The flicker doesn't occur on any phones. Ariel Levin: As I noted, this is a bug in the 2.2 beta. It has been fixed for the final release. DavidH: Do cell phone VM's need to be updated to take advantage of WTK2.2? Jonathan Knudsen: Mobile devices will support some collection of APIs. For example, a device might support MIDP 2.0, JSR 184 (3D Graphics), and JSR 135 (MMAPI). When you develop an application using the J2ME Wireless Toolkit, you specify which APIs you will be using, based on which devices you'd like to use to run your application. WTK Bug baster: What about support for JSR 72? When will it be in the toolkit and on devices? Cori Kaylor: Do you mean JSR 172? Web Services is already supported in WTK 2.1. If you are referring to JSR 82 (Bluetooth), it will be supported in WTK 2.2. DavidH: Hi folks, sorry, I just joined the chat so I'm not sure if this was addressed -- do you have any control over adoption by cell phone manufacturers of MMAPI video capture APIs? It seems that they are slow to adopt. Ariel Levin: No, we don't have that sort of control over them. It's up to them to decide which optional JSRs they implement. Having said that, MMAPI is part of the JTWI JSR (185), which could help promote that. DavidH: What's JTWI JSR 185? Jonathan Knudsen: It's a specification that describes a standard J2ME stack, which is a collection of APIs. spint: Is there any support for URL encoding in MIDP 1.0? Jonathan Knudsen: No, MIDP 1.0 does not have an API for URL encoding. You'll have to do it manually. tellman: I know SE has implemented an ODD (On Device Debugging) interface. Do you plan to have some sort of standard ODD added to the next MIDP incarnation? Ariel Levin: This would be up to the MIDP expert group. If and when a next version of MIDP is devised, you can always send your input to the expert group. tellman: "..If and when.." ??? ;) So I guess there aren't plans for the next version? Ariel Levin: Not as far as I know, but then I don't know everything that goes on in the JCP ... ;-) tellman: Is there a WTK2.3 coming soon? If yes - except fixed bugs - what new additions are expected? When? Cori Kaylor: After this version of 2.2 is released we want to start working on WTK 2.3. We will look at adding technologies like the next version of JTWI, JSR 177. You can probably expect to see something Spring of next year. Guest: I spent a number of years in Tokyo, Japan, and did some development on DoCoMo phones, which used DoJa, a variant of J2ME. However, I am back in the U.S. now and developing standard J2ME applications. Is DoCoMo going to support standard J2ME in all its phones in the near future, especially since Vodaphone and AU already do? DoJa is fragmenting the J2ME market in Japan and complicates development. Jonathan Knudsen: You'll have to ask DoCoMo about their plans. MIDP has a lot of momentum as far as deployed devices and carriers. Check java.com for some quick (and impressive) statistics. Falken: The Jonathan Knudsen: Yes, Chapter 2 of the Basic Customization Guide describes how to create or modify emulator skins. You can find the Basic Customization Guide in the docs directory of the toolkit installation. tellman: With security getting better in MIDP (with the addition of signed MIDlets), and developers desperately trying to simulate procedural methodology in their code (instead of pure OOP), due to the mobile device constraints, do you think next MIDP version will support dynamic class loading? Or was this question closed forever? Ariel Levin: This is something that would probably be targeted at the configuration level, like CLDC, and not at the profile level. This is something that could become feasible as devices get stronger, but it would be the experts' group call. Guest: Any chance to see the Toolkit ported to other than Linux or Windows? Why not port to Apple OS X and Solaris also? Jonathan Knudsen: For OS X you might want to check out the Mpowerplayer (not associated with Sun). jimmy: Are there books related to Bluetooth technology? Jonathan Knudsen: For J2ME books, check out the MIDP Bookshelf and the hashbang.com.au J2ME book list. rwmarejka: Could new JSR support be delivered as JAR files to plug into the WTK? Are there any plans for this post 2.2 release? Ariel Levin: Unfortunately, no. This is due to the way the emulator is built, which has all the APIs "ROMized" into it, just like it would be on a device. cellman: When will 2.2 be fully available? Cori Kaylor: Our current plan is to release 2.2 final in the next couple of months. Falken: Are you planning to produce a WTK that will support JSR 234 Advanced Multimedia? It's moving fast, isn't it? Cori Kaylor: We currently don't have any plans to support JSR 234. We are trying to follow and support the JTWI Roadmap 2 roadmap. DavidH: How would I find out how to draw on top of live video capture? Ariel Levin: I would suggest trying to post a question on the kvm-interest list. Jonathan Knudsen: You can also post feedback to the team. MDR-EdO: Well we've quickly come to the end of the session. I'd like to thank all of you who participated today. I thought we had a nice range of questions. And of course I'd especially like to thank our guests Ariel, Jonathan, and Cori for their answers. Ariel Levin: Happy to be here and answer the questions. Now go download the WTK 2.2 beta and get those incredible MIDlets going ... Cori Kaylor: Thanks Guys, this was really great. Let us know if you have any additional feature requests or concerns and we will do our best to help you! Let us know what you think about WTK 2.2. Jonathan Knudsen: Thanks for the great questions everyone! If you haven't tried the 2.2 beta, go get it! MDR-EdO: Last moderator (me) signing off. The forum is now unmoderated. | ||||
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