Java classpath wildcard not working without quotes

Question

I have a folder with lots of jar files and a classpath:

-classpath ./classes:./jogamp-all-platforms/jar/*

But it doesn't find the package. Just to make sure that I have the resource in question I manually find the jar that contains it and change the classpath to:

-classpath ./classes:./jogamp-all-platforms/jar/jogl-all.jar

And now it isn't complaining about not finding a package.

Answer 1

Under Debian I had to put quotations marks just around the wildcard for this to work: "*"

Then the compile command becomes:

javac -cp ~/my\ stuff/Java/"*" test.java

I'm using JDK, JRE 8.

Answer 2

The issue is that * is expanded to all the entries in your directory and the classpath syntax allows directories and jar files separated with : on your platform. * is expanded and will include all the jars in your directory and you will end with something like:

-classpath ./classes:./jogamp-all-platforms/jar/jogl-all.jar another.jar etc.jar

If in your ./jogamp-all-platforms/ directory you have the jogl-all.jar another.jar etc.jar jars.

You can escape the * expansion by the shell using something like:

-classpath './classes:./jogamp-all-platforms/jar/*'

This way your compiler will interpret the * expansion.

Answer 3

I think you need to use ; as path separator after ./classes as below:

 -classpath ./classes;./jogamp-all-platforms/jar/*

Also please note:

Subdirectories are not searched recursively. For example, jogamp-all-platforms/jar/* looks for JAR/Class files only in jogamp-all-platforms/jar, not in jogamp-all-platforms/jar/abcd, jogamp-all-platforms/jar/efc, etc.

By doing -classpath ./classes:./jogamp-all-platforms/jar/* , it looks of all the JARs in jogamp-all-platforms/jar folder only.

For more details, please refer the documentation here- Wildcards in classpath .

Answer 4

The first form will not work. You cannot load jar files with wildcards. The second form should work, unless you're missing dependent classes.