Small JAR problem

[Kaizer]

Hello all !
I discovered how to make .jar files, using the cmd console.
I made a .jar simply by defining the entry point class with the following syntax:

jar cfe Test.jar TimeViewer *.class

double clicking the actual .jar file via windows explorer yields : "Cannot find the main class: TimeViewer. Program will exit." error message, but running the jar through the console with the appropriate syntax works fine. Its exactly the same if I make the Manifest.txt myself and create the .jar with

jar cfm Test.jar Manifest.txt *.class

Fine through console but not double clicking.

can someone please help?
thanks! ^^

[2by4]

Hello all !
I discovered how to make .jar files, using the cmd console.
I made a .jar simply by defining the entry point class with the following syntax:

jar cfe Test.jar TimeViewer *.class

double clicking the actual .jar file via windows explorer yields : "Cannot find the main class: TimeViewer. Program will exit." error message, but running the jar through the console with the appropriate syntax works fine. Its exactly the same if I make the Manifest.txt myself and create the .jar with

jar cfm Test.jar Manifest.txt *.class

Fine through console but not double clicking.

can someone please help?
thanks! ^^

Does your manifest have a Main-Class entry?

If so, is it terminated with a carriage return?

[Kaizer]

yes, here be the content of my (self made) Manifest :

Main-Class: TimeViewer

and I pressed 'enter' after TimeViewer for carriage return, so its actually two lines, second one being empty but making sure the 'blinking' vertical line is at the start of the second line.

[2by4]

Is there a package statement in your source?

[Kaizer]

In the source code you mean? No, no mention of packages.
If I change the manifest to

Main-Class: JClock.TimeViewer

to include the package name, it won't even run from cmd. The error message I get is
Error:Could not find or load main class JClock.TimeViewer

PS: I realise case sensitivity is very important and I've made sure that everything corresponds.

[Kaizer]

arggh.. I just followed a simple video tutorial involving just one class file, I did everything same as the 'tutor', and as usual same problem. I can run the jar file from the console it launches it accordingly, but double clicking from windows explorer I keep getting the same 'Could not find the main class: Hello'
The tutorial included showing how to make a proper manifest so I know I got it right.

[Kaizer]

ironically, double clicking a JAR file made by someone else involving my code (so exactly the same) works.. just not when I make it.

[2by4]

What does jar tf Test.jar give you?

[Kaizer]

that gives me (working on the single class case now) :

META-INF/
META-INF/MANIFEST.MF
Hello.class

[2by4]

...hmmm....so...

When you double click a jar, it launches javaw.exe..

Is the other persons version of Java different from yours? Do you both get the same thing with java -version

[2by4]

OK, I'm off for a while..but before I go, ideas...

1. Your version of Java is different from your version of javaw.exe

2. If you move your jar to an empty directory, can you still run it from the command line?

3. If you extract using jar xf Test.jar, (in your empty directory, so that you don't overwrite anything), does your manifest file have the expected entries.

[Kaizer]

awesome, got it to work now. there was a problem in version as you guessed. I must have been confused when installing Java initially and editing the "environment"'s path, between Program Files and Program Files x86. I fixed it and updated at same time so now it shows "vers. 1.7.0_02" :)

so I got it to work on that example I was working on, with the hello.class; and my 'JClock' =) thanks for all the help ! xD