You need to run the jmf customizer. BTW, create a backup of jmf.properties in the lib subdirectory first.

You can also use sin/cos routines for fixed-point numbers. If you google you will probably find some open source J2ME class with them in.

There is another possible option: the IKVM project (http://www.ikvm.net/). It is a JVM for .Net and also includes a bytecode to .Net CIL compiler. So you might be able to have your cake and eat it.

You will probably want to get one which supports the latest and largest number of APIs (MIDP 2.0, MMAPI, bluetooth, etc). On the other hand you may wish to get the most popular phone. Depends whether you are more interested in developing for personnal use or more concerned with the largest number of people being able to run your apps consistently (J2ME implementations tend to vary).

I looked through some stuff about this, and as far as I can tell it is not a hardware JVM. It just has similar principles.  

Maybe Windows swapped out the process during the sleep, hence it had to take time to swap it back in.

Yes, it is scary. But, MySQL allows you to setup permissions for SQL statements, so you can prevent people from executing arbitrary sql statements.

If you have a mysql database on a web server, then a java client can connect to it using jdbc with no java required on the server. That is, the JDBC driver is on the client not the server side.

To get yourself started, download JDBC MySQL connector from www.mysql.com, and play with client code like:


String host,database,username,password;

String url = "jdbc:mysql://"+host+"/"+database+"?user="+username+"&?password="+password;
Class.forName("com.mysql.jdbc.Driver");
Connection con =DriverManager.getConnection(url);
.
.
.

I have a Zaurus SL-5500, and I love it They really are like carrying around a linux terminal in your hand. It'll run almost anything you can throw at it. I have had mine running a Java IRC server without problems.

BTW, did I mention Zaurus rulezzzzzz!!!!!!

See the FAQ at the bottom of the page http://java.dnsalias.com/

It has info about timers and thread.sleep/yield and the 100% CPU thing.

I think the patents refer to object registries so perhaps the rmi stuff is the source of contention. I guess COBRA would be a problem as well then.

Do you have a Thread.sleep() or Thread.yield() in your rendering loop? If you have a tight rendering loop, it could be starving the music thread of processing cycles, so it only starts playing at the end of the show. Also check you have synchronized in the right place, could also be a deadlock.

So, such a beast would be a good (interesting) test of the portability of the JVM.



--
I guess if everything is Turing-complete, then it is trivial from a theoretical point of view.

I know of http://javaisdoomed.sourceforge.net/, might provide you with a good starting point.

If you create jnlp <component-desc/> files for the third-party jars, they do not need to be signed if they don't require <all-permissions/>. This is independent of whether the main app jar is signed. For example, you can have a signed network game app jnlp bundled with an unsigned gage2d jar component-desc jnlp. The other advantage of component-desc jnlp files is that different apps can re-use the same component-desc jars.

I believe if you use the URLClassLoader with a JAR URL, then manifest attributes such as Class-Path are automatically respected. At least that is what seems to happen with my plugin loader.

Yes, as a rule of thumb, you organise objects by behaviour. Then when you come to code, you implement the behaviour by writing methods for the objects.

If you haven't looked at it already, check out the tutorial at http://java.sun.com/docs/books/tutorial/index.html

I have used something like the GAGE sprite interface. I have various sprite classes for all my game objects. My parent sprite class is a composite of a java.awt.geom.Area instance (object geometry for stuff like collision detections) and a renderer instance which the sprite delegates to for rendering. Game object behaviour is determined by the methods in the sprite sub-classes.

I use renderer factories to construct the renderer delegates. At the moment I have two factories, the normal game one and a geometric one. The geometric one renders sprites according to their java.awt.geom.Shape and I use it to debug collision detection.

I have no sound currently and I handle input in the game frame class using boolean switches. Oh, I also went as far to abstract the rendering loop, so I can easily swap in different frame scheduling algorithms.  

I would like to point out that alternate Webstart-ware does exist, see for instance http://jnlp.sourceforge.net/netx/. So, it's not completely out of the hands of developers. Ofcourse, then there's the problem of deploying that on user's machines which brings us back to installers.

File.exists()

You will probably find the two articles below very useful. The first one has a section about explicit nulling, and states "But in most cases, it doesn't help the garbage collector at all, and in some cases, it can actually hurt your program's performance."

Garbage collection and performance
http://www-106.ibm.com/developerworks/java/library/j-jtp01274.html

Garbage collection in the 1.4.1 JVM
http://www-106.ibm.com/developerworks/java/library/j-jtp11253/

Oh well, it was a nice thought..... I guess on Windows then, this has implications for syncing media and stuff??? I suppose if this was problematic one could write a GAGETimeBase class, but I guess the use of SystemTimeBase is probably hard-coded.

I would have thought you should use TCP for chat, since its a reliable protocol. You don't want to be losing bits of players conversation. In fact, I assumed you actually meant to type it this way round:

udp: for game logic data exchange (pos of player, gun fired etc)

tcp: for live chat and stuff.

I got caught out by that one as well. The best explanation I could come up with is that its register() not reregister() :-/. I guess on the positive side, at least the javadocs are clear on this point.

Java3D and JMF also come with timers that should be better than System.currentTimeMillis().

If you are looking for a Java solution, I think it's possible to use Java Media Framework for this. Check out the screen grabber example at http://java.sun.com/products/java-media/jmf/2.1.1/solutions/ScreenGrabber.html. It says it can even stream captures over the internet.

This may help: http://jsmooth.sourceforge.net/. It embeddes a jar file into an exe. It does not bundle the java runtime as well, though.

Hi,

If you are looking for a Java based IRC server, try http://j-ircd.sourceforge.net/ for size.

My understanding of the IRC protocol mess is that the (new) RFCs were written after-the-fact, to try to consolidate the differing protocols used by various implementations. Needless to say the RFCs are vague in several areas.

The idea of using IRC to provide game chat sounds interesting. I guess one of the advantages would be that a separate chat server would reduce the burden on the game server...