File output = new File((String) nonOptionArguments.remove(0));
Assert.isTrue(output.getName().toLowerCase().endsWith(".jar"), "The output '"
+ output + "' is not a JAR file.");
deleteIfExists(output);
GroovyCompiler compiler = createCompiler(options);
List<URL> classpath = getClassPathUrls(compiler);
List<MatchedResource> classpathEntries = findMatchingClasspathEntries(
classpath, options);
String[] sources = new SourceOptions(nonOptionArguments).getSourcesArray();
Class<?>[] compiledClasses = compiler.compile(sources);
List<URL> dependencies = getClassPathUrls(compiler);
dependencies.removeAll(classpath);
writeJar(output, compiledClasses, classpathEntries, dependencies);