in src/main/java/com/microsoft/azure/functions/worker/description/FunctionMethodDescriptor.java [146:154]
void guardAgainstUnqualifiedJarPath() {
if (jarPath == null) {
throw new NullPointerException("JarPath cannot not be null.");
}
if (StringUtils.isBlank(jarPath)) {
throw new IllegalArgumentException("\"" + jarPath + "\" is not a qualified JAR file name");
}
}