Applets vs. Applications

Newbie & Debugging Questions
#1

Hi all! I r a newless clubie!

So I thought I’d ask a few basic questions. I could try these out on my own, but it would jump start me if I could just get expert opinions (ie, I’m lazy).

Applet games: I assume Java3D is available. Is OpenGL available to applets?

How hard is it to maintain the same game as both an applet and a stand alone app? Are there any pitfalls I should pay attention to?

How about writing applet games in general. Is the response to input good? Or laggy? Any advice here?

What about security? An applet can contact it’s host sever, but can I log-in an individucal user securely? What object can I use (I can’t make my own datagrams, can I)?

Ok, that’s all for now. I’m off to cruise the boards and see what other info I can find. Thanks for the help!!

#2

check out my site listed in my signature. I’ve never noticed any lag. The only difference I’ve ever seen is that graphics can be drawn faster in standalone apps than they can be in Applets.

#3

Hey nice site! Yes those games seem pretty responsive, no worries there. Did you have to do anything special or are just basically reading from standard-in?

#4

reading from standard-in

Huh?

Nah… you use things like the KeyListener for turning flags on and off (eg set a boolean to true if you get a pressed event and set it to false if you get an released event). In your main loop you just react to the values of those switches.

See here:
http://www.java-gaming.org/cgi-bin/JGNetForums/YaBB.cgi?board=cluebies;action=display;num=1100581905;start=6#6

#5

yup. KeyListeners and MouseListeners are how I do it, just as oNyx described

#6

Good point about the keyboard listener. I’m a C programmer, mostly. :slight_smile: I remember mouse listeners from the Java book I have, but I’ll have to go back and look up keyboard listeners.

Hey, no one knows if OpenGL (JOGL?) is available to an applet? It’s a native method right? so I assume not, but I’m still resisting writing code just to see if it 'splodes.

#7

I think the basic question is why do you need an applet? Why not a Java Webstart application? Such an application is easy to maintain both as an stand alone application and a webstart application. If you don’t know the differens between an applet and a webstart app you should search the forums.

#8

I have a java web start app that I use and love (Bill Shubert pwns u!!).

Basically, Bill’s app allows you to use it as an applet, or as a webstart app. The applet is very convienent. There’s nothing to install, no worries about “wtf is this JRE thing” for the user. Just click and go and the applet runs. THAT’S what I want, because I found the user experience to be excellent when I used Bill’s app.

Now of course I’ve installed the full JRE and webstart apps are no worries for me, but not all users have webstart installed. Thus I’d like to support applets too.

#9

Java3d and OpenGL are not available to applets. That is unless you make the user install it manually. This involves copying files into one of the jre sub directories.

An applet and a stand alone app is pretty much the same. Abstract away the differences. Instead of painting on the applet, you point on a canvas that is added to the applet. The same canvas can be added to a frame in a stand alone app. Be aware that applets have security restrictions. So you can’t read files on the disk or sending udp to any odd address.

Also note that many people still only got java 1.1 installed.

#10

Yeah, I think the bnok on Java I have right now may not be the best. I’m finding it does not cover many things. I’ve seen Dietel & Dietel rated as excellent, if a bit more of a reference manual and less of a tutorial. Amazon has used copies cheap.

Amazon also rates highly a couple of books: Java 2 A Beginner’s Guide – by Herbert Schildt, and Java 2 The Complete Reference, Fifth Edition – by Herbert Schildt.

Any suggestions?

#11

We used the Dietel & Dietel book in college. I liked it. Easy to understand with plenty of examples.