Java for Maemo 5 - Page 6 - maemo.org

fms | # 51 | 2009-10-17, 15:11 | Report

Originally Posted by SubCore View Post

well, i myself would actually need it for "custom corporate middleware"

I see.

Originally Posted by

basically, you're right about the reason why java doesn't come with the n900 out-of-the box (and why it didn't on earlier tablets). there are not really many use cases for it on such devices, but they do exist

which makes pursuing this goal worthwhile.

You should then download Jalimo and start hacking, shouldn't you?

SubCore | # 52 | 2009-10-17, 15:25 | Report

as soon as i get my n900, i will

openjre also sounded very interesting, for that matter.

RevdKathy | # 53 | 2009-10-17, 15:29 | Report

Being trying to follow this thread, but I got lost in the various sorts of java. I think the sort you're talking about is the sort that BlackBoard runs on, which is he software used at universities and colleges for distance larning. That's what I'd want it for.

Rushmore | # 54 | 2009-10-17, 15:41 | Report

Originally Posted by jaark View Post

Java is always 'layered' ontop of whatever platform you are running, and will always be slower than the base system.

That is the trade-off for 'compile once, run almost anywhere' for many applications the trade-off pays off, for others it doesn't.

Yep. Non cpu intense apps it would be fine, but for things like emulators or medai apps using codecs it would not.

fms | # 55 | 2009-10-17, 16:29 | Report

Originally Posted by RevdKathy View Post

Being trying to follow this thread, but I got lost in the various sorts of java. I think the sort you're talking about is the sort that BlackBoard runs on, which is he software used at universities and colleges for distance larning. That's what I'd want it for.

Well, there are three sorts of Java the normal consumer should care:

1. Android Java, running on top of its own virtual machine (aka Dalvik). As long as you do not have Android, you can disregard this variety.

2. JavaME also known as MIDP, also known as J2ME, also known as PhoneME is a somewhat lobotomized version of Java supported by most mobile phones. Most mobile games and some mobile apps running on dumb phones are written using this version of Java.

3. JavaSE is the desktop Java. If you ever run a Java application on your PC or Mac, or a Java applet in your browser, it is most likely written in JavaSE. The number of widely used Java applications is near nil though, mostly due to problems with performance, compatibility, and maintenance, so you are unlikely to ever use this one.

Of these three, only #2 (JavaME) is of practical interest to a big number of users, because everybody is used to MIDP games on their phones. Unfortunately, there is still no standalone JavaME package for the tablets, that would instantly allow users to play .jar and .jad files with MIDP games.

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RevdKathy | # 56 | 2009-10-17, 16:52 | Report

Ahh right. Android java I have no experience of.

J2ME is a term I recognise. That's what my shopping list runs on, in my current devices. (And jtwitter, which I can't wait to put behind me) Yes, it would be nifty if n900 could carry that.

JavaSE would indeed be what Blackboard runs. It has a forum system - I never worked out why it needed to be java. I can't reply to anything from an NHS computer because the java on those is out of date (they run XP with IE6

and regular staff don't have admin access to update.) I was under the impression that n900 could handly that sort of java? Did I not see it running a chat applet in one of the videos? (Or did I dream that bit?)

SubCore | # 57 | 2009-10-17, 16:57 | Report

Originally Posted by fms View Post

The number of widely used Java applications is near nil though

don't underestimate just how much of the aforementioned corporate middleware there is

the second example of mine, citrix access gateway, is fairly widespread.

probably a question of the definition of "widely"

pupu | # 58 | 2009-10-17, 17:11 | Report

Java applications are used a lot on the web. The smaller things like tic-tac-toe kind of games are irrelevant, but for example, Runescape is done in Java, and so are chat applications on some sites. IMHO, a device can't really claim to offer the full web experience without Java.

Consumer desktop applications tend not to use Java, but as others have said, many of us do use Java applications in a work setting. From my personal user's perspective, I really haven't witnessed poor performance. For example the RealVNC Java application has worked just fine for me. There's a longer wait when you start a Java application for the first time during your OS session, but even that disappears on subsequent use.

bcaroll | # 59 | 2009-10-17, 17:14 | Report

The iPhone is the phone everybody wants to beat, so what must Nokia do to make Maemo better. I have some ideas and one of them is Java.

Every iPhone developer a have talked to complains about the awful IDE that Apple provides Xcode. That feel like going back to how Java IDEs looked 10 years ago. They also complains about having to work in C and specifically memory management. If development is done is Java everybody can use their favourite IDE (Eclipse, NetBeans, IntelliJ, etc) and on device debugging can be used easily.

JavaME is a must so that it can be used until the native Maemo apps are created. I won't buy a phone that don't have JavaME.

There should also be JavaSE on the device and QT bindings for the developers that want leverage all the native power. With JNI most of an app could be written in Java with callout to the native platform for performance or hooks into native functions.

JavaFX would be nice but I don't think that it would make difference on the sales of the devices.

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Bratag | # 60 | 2009-10-17, 22:15 | Report

Originally Posted by bcaroll View Post

The iPhone is the phone everybody wants to beat, so what must Nokia do to make Maemo better. I have some ideas and one of them is Java.

Every iPhone developer a have talked to complains about the awful IDE that Apple provides Xcode. That feel like going back to how Java IDEs looked 10 years ago. They also complains about having to work in C and specifically memory management. If development is done is Java everybody can use their favourite IDE (Eclipse, NetBeans, IntelliJ, etc) and on device debugging can be used easily.

JavaME is a must so that it can be used until the native Maemo apps are created. I won't buy a phone that don't have JavaME.

There should also be JavaSE on the device and QT bindings for the developers that want leverage all the native power. With JNI most of an app could be written in Java with callout to the native platform for performance or hooks into native functions.

JavaFX would be nice but I don't think that it would make difference on the sales of the devices.

So you want speed and java. Yeah thats not going to happen. As an android coder who also codes in C I can tell you there is no comparisson in performance. The reason java coders hate to code in C is because it forces you to think about memory allocation and freeing and that goes against the " throw everything into memory and let garbage collection sort it out " mentality that most Java coders have.

Trust me the surest way to take something fast and hobble it is chuck Java into the mix. Here is an example.

I have a pixel by pixel filter I compiled on my G1 in C and also the same filter in Java. The C version runs in 2 seconds on a selected image, the Java version takes 20 and on top of that half the time it craps out because the jvm runs out of memory.

Take from that what you will I guess