Question

I have a project that uses the serial port, and it requires two files to run, the win32.dll file (which is in the java runtime environment bin folder) and the javax.comm.properties file (which is in the java runtime environment lib folder). When I run the project from eclipse it works, but when I try to build a jar file for distribution, it won’t work. I suspect this is because the dll and properties files aren’t included in the jar. How do I specify that they need to be there?

Answer 1

You generally don’t put dll and properties files inside the jar. Properties files as well other jar files need to be added to the classpath. The jar file has a manifest file that defines the classpath used. You can’t edit this with eclipse. You need to define an ant build.xml file and do something like this:

<jar jarfile='${dist}/MyJar.jar' basedir='${build}'>   <manifest>     <attribute name='Main-Class' value='MyClass'/>     <attribute name='Class-Path' value='.'/>   </manifest> </jar> 

Then put the properties file in the same folder as the jar. You can run the ant target by right clicking the build.xml and selecting the ‘Run as Ant target’.

If I remember correctly, placing the dll file in the bin directory of the jre will work.