code: public InputStream openStream() throws IOException {
          final SecurityManager sm = System.getSecurityManager();
          if (sm != null) {
              sm.checkPermission(new VirtualFilePermission(getPathName(), "read"));
          }
          if (isDirectory()) {
              return new VirtualJarInputStream(this);
          }
          final VFS.Mount mount = VFS.getMount(this);
          if (sm != null) {
              return doIoPrivileged(() -> mount.getFileSystem().openInputStream(mount.getMountPoint(), this));
          }
          return mount.getFileSystem().openInputStream(mount.getMountPoint(), this);
      }
docs: Access the file contents.
  
  @return an InputStream for the file contents.
  @throws IOException for any error accessing the file system