Making executable java code??

create a .jar file

any chance of a little more detail?

A Jar isn't executable, it just packs everything together in one file.

The way we do it for our level editor is just create a batch file (Create a text document with the extension .bat) with these contents (We use JARs):

Then at least you can double click the batch file to launch the app.

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Original post by Evil Steve A Jar isn't executable

They are if you've created them properly. And unlike your batch file they're cross platform.

http://java.sun.com/docs/books/tutorial/deployment/jar/

However you might find that Java Webstart would be a better distribution method and provides more functionality 'for free' than executable jars. For a start you get one-click downloading and running, and it'll auto update without any extra effort. If you've already got a jar version working then webstart is easy to add to it.

http://java.sun.com/docs/books/tutorial/deployment/webstart/index.html

A JAR file is just a specialized ZIP archive, how can it be execuatable? The closest that link mentions (that I can see) is:

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JAR Files as Applications You can run JAR-packaged applications with the Java interpreter. The basic command is: java -jar jar-file

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Original post by Evil Steve A JAR file is just a specialized ZIP archive, how can it be execuatable? The closest that link mentions (that I can see) is: Quote: JAR Files as Applications You can run JAR-packaged applications with the Java interpreter. The basic command is: java -jar jar-file

By default the JRE installer creates an association between .jar files and the VM. Double clicking a jar then starts up the VM with that jar, and the manifest file you create in it specifies which class's main() method to start from.

However some tools (most notably WinRar) tend to steal this association and replace it with their own (a very broken and stupid behaviour, IMHO). If someones done that then you're out of luck. Of course if the user has fucked around with the association manually then it's their own fault.

This is one of the reasons why webstart is nicer, as .jnlp files (also registered when a user installs a JRE) don't get stolen by other applications.

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Original post by OrangyTang Quote: Original post by Evil Steve A JAR file is just a specialized ZIP archive, how can it be execuatable? The closest that link mentions (that I can see) is: Quote: JAR Files as Applications You can run JAR-packaged applications with the Java interpreter. The basic command is: java -jar jar-file By default the JRE installer creates an association between .jar files and the VM. Double clicking a jar then starts up the VM with that jar, and the manifest file you create in it specifies which class's main() method to start from. However some tools (most notably WinRar) tend to steal this association and replace it with their own (a very broken and stupid behaviour, IMHO). If someones done that then you're out of luck. Of course if the user has fucked around with the association manually then it's their own fault.

Ahh, right. I never knew that, so I always tell WinRAR that it can have that extension. Thanks for clearing that up [smile]

Yes, webstart is nice, but has it's limitations and problems. For example, jar files are supposed to be signed when deployed using webstart. It's mandatory, if I recall correctly.

There are some more interesting issues that come up when you're trying to execute a JNLP file from within a browser (when your jnlp file gets downloaded to a browser in order to launch a web application).


In any case, if the jar file should just be an executable program (without any web deployment), I'd suggest using one of the many exe wrappers out there, that create an exe file for you that attempts to run the JAR file.

They usually perform checks of whether the JRE is installed, what version, etc. Basic solution unless you can settle for batch files (good under Windows only).

A jar can be executable, on both windows and macintosh by double clicking on the jar file. This is done via the manifest file. For proof of concept you can download a demo of my program at http://www.faceinthesword.com, install it, and execute the program by double clicking a jar file. The program itself is of little interest to most people.

Feel free to unpack the executable jar labeled "jAptSchedule" and look at its directory structure and where the manifest file is located.

Here is part of Sun's tutorial on making a jar file executable.

http://java.sun.com/docs/books/tutorial/deployment/jar/appman.html

This tutorial should show you where to place the manifest file.

In linux you will either need to enter java -jar *.jar at the command line or you can write a shell launcher.

Netbeans automatically makes jar files executable, and I believe eclipse has a plugin to do the same.

Happy Hunting

Greg

GCJ (part of the GCC) can compile Java to native machine code.

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Original post by lonesock GCJ (part of the GCC) can compile Java to native machine code.

And here is an example of how to set that up.