Question

I am new to Java, I just finished my first little project, and I would like to compile it into a JAR file. I did it from Eclipse with the Export method, I have selected my class containing the Main method, but when my JAR file is created, when I double click on it, the program just don’t run. Nothing happen, I get no error.
Here is my Manifest file, auto-generated via Eclipse:

Manifest-Version: 1.0
Main-Class: Main

Thanks in advance for helping.

Answer 1

You probably have external JAR dependencies that resolve just fine in Eclipse, but fail when you run the JAR from the command line. There are a couple of solutions for problems like this:

1. Add the path to each dependent JAR in your system classpath. This is
   the least desirable and least portable method.
2. Specify the path to each dependent JAR as a setting in your Manifest
   file. This is only a hair more portable than method 1), but can work
   well if you bundle your applications JAR file into a ZIP, along with
   all the dependent JAR’s.
3. Bust open the dependent JAR’s, extracting the classes and including
   them in your JAR. This is a very ugly solution but has been used by
   many open source projects in the early days of Java.
4. Use a solution like OneJar to create a truly executable JAR
   with all dependencies accounted for. Somewhat proprietary but
   probably your best bet.

Good luck!