code: public static boolean copy(FileSystem srcFS, Path[] srcs, 
        FileSystem dstFS, Path dst,
        boolean deleteSource, 
        boolean overwrite, boolean validate, Configuration conf)
        throws IOException {
        return copy(srcFS, srcs, dstFS, dst, deleteSource,
            overwrite, validate, conf, null);
    }
docs: copy a list of files from a source file system to a directory dst
  in a destination file system
  
  @param srcFS source file system
  @param srcs a list of source files
  @param dstFS destination file system
  @param dst destination directory
  @param deleteSource if source should be deleted
  @param overwrite if destination should be overwritten
  @param validate if destination file should be validated
  @param conf configuration
  @return true if copy succeeds
  @throws IOException if error occurs