Java 使用VFS.getManager（）时设置baseFile

我正在创建我的经理，就像示例一样

FileSystemManager manager = VFS.getManager();

我现在如何设置baseFile以避免该消息

org.apache.commons.vfs2.FileSystemException: Could not find file with URI "./download" because it is a relative path, and no base URI was provided.

因为我使用文件系统选项

manager.resolveFile(route.getSource(), fileSystemOptions);

没有采用基url的resolveFile方法。我已经试过了

DefaultFileSystemConfigBuilder.getInstance().setRootURI(opts, ".");

但这没用