Loading resources from multiple JARs

Newbie & Debugging Questions
#1

Cross-posting with sun forums since I’m getting no response, maybe you guys can help with this issue as I’m sure other games have needed this behaviour.

I am attempting to load various resources (images, sounds, files) from a separate JAR from my source class. I have two jars:

source.jar <- contains all my class files
resources.jar <- contains all my images/sounds.

If I do not split these into two jars, everything works as expected. I am using the following HTML tag:

And the following resource loading code with and without the slash ‘/’:

applet.getClass().getResourceAsStream(“images/temp/test.png”) <- Does not work, Returns null.
applet.getClass().getResourceAsStream("/images/temp/test.png") <- Works when I have everything in the same JAR, but not when they are separate. Returns null.

I am splitting up the JARs so the large resources can download separately via JAR Indexing. But, I cannot access this test image with or without indexing when the JARs are separated. Directory structure is:

source.jar:
Main/MyClass.class
Lib/OtherClass.class
Data/SomeData.bin
^ all load fine

resources.jar:
images/temp/test.png
sounds/mysound.ogg
^ cannot access these =(

Am I missing something here?

Jesse

#2

I’m not sure about applets, but I’ve used multiple JARs in Java Webstart applications on several occasions. In that case, you just need to list both as resources in your JNLP file, and then directories are preserved.

As far as I know you don’t want that leading slash in there, because doing that tells it to go to the root directory and then look from there, rather than the current directory. Have you tried adding on a “user.dir” call?

#3

From what I’ve read, having no leading slash prepends the class’s package name converting all .'s to /'s. I suppose this is useful when you want to load resources that are in subdirectories from your class files, but I have my resources in a separate directory. I tried having no slash and this fails whether I have the files together or in separate JARs.

I haven’t tried applet.getCodeBase() + “images/temp/test.png” (is that what you mean by user.dir?) … maybe I’ll give that a shot… but I don’t see how it knows then to open up a JAR and not some resource sitting on a server.

And as I’m sure you know there are no JNLP files for applets =(. Everything I’ve read seems to imply that getResourceAsStream() should search the full classpath, including both JARs, to look for resources… so I must be doing something wrong here.

Jesse

#4

Tried to remove the space from the archive attribute?


<applet code="Main.MyClass.class" ARCHIVE="source.jar,resources.jar" width="800" height="600">
#5

Sorry it took so long to reply. I just tried with no space in the ARCHIVE tag, and it made no difference.

No one has deployed a game through an applet like this? =(

#6

Umm so I named it resources.Jar with a capital J. Wow I’m bad. Umm… yeah. embarassed

#7

I use multiple jars. The following always works for me:

<object>.getClass().getClassLoader().getResourceAsStream(path);

path is the relative path e.g. “image/interface/button.gif”…

Please note the getClassLoader() statement that I am using. Mabye omitting the statement prevents you from getting it to work?