如何从命令行使用jarjar？

Question

I'm having trouble using jarjar from the command-line to combine a simple Scala program with the scala runtime-library.

jarjar correctly detects the dependency:

$ java -jar ~/Desktop/saug/jarjar-1.0.jar find jar BCT.jar scala-library.jar
/home/schani/Work/scala/bct/BCT.jar -> /home/schani/Work/scala/bct/scala-library.jar

Combining them doesn't work, however:

$ CLASSPATH=./scala-library.jar java -jar ~/Desktop/saug/jarjar-1.0.jar process rules.jjl BCT.jar BCTS.jar

The jar file that I get still depends on scala-library.jar. Whether or not I add the CLASSPATH variable makes no difference. My rules.jjl file looks like this:

keep BCT

What to do?

Answer 1

Using the java "-jar" option ignores the classpath. Try specifying the main class explicitly with a classpath, and omit "-jar":

java -cp ~/Desktop/saug/jarjar-1.0.jar:./scala-library.jar com.tonicsystems.jarjar.Main process rules.jjl BCT.jar BCTS.jar

Answer 2

Try adding a keep for the scala.runtime.Nothing$ class. I found this necessary when using a similar product (autojar; http://autojar.sourceforge.net/en_d/index.html ) with Scala.

Answer 3

jarjar does not repackage other jars into your jar. It only renames dependencies inside the one jar itself.

Use the method outlined here Clean way to combine multiple jars? Preferably using Ant to rejar all the dependent jars into your jar, then run jarjar to prevent future dependency hell.