code: public void addFile(String sourceFolder, String name, ClassLoaderFile file) {
  		Assert.notNull(sourceFolder, "SourceFolder must not be null");
  		Assert.notNull(name, "Name must not be null");
  		Assert.notNull(file, "File must not be null");
  		removeAll(name);
  		getOrCreateSourceFolder(sourceFolder).add(name, file);
  	}
docs: Add a single {@link ClassLoaderFile} to the collection.
  @param sourceFolder the source folder of the file
  @param name the name of the file
  @param file the file to add