public void copyToLocal(final String fromLocation, final String toLocation) {
        try {
            this.fs.copyToLocalFile(new Path(fromLocation), new Path(toLocation));
        } catch (final IOException e) {
            throw new IllegalStateException(e.getMessage(), e);
        }
    }
@param pattern refers directory or a set of files
@return a non-null array of the files and directories the pattern refers as of {@link Storage#ls(String)}
hadoop-gremlin/src/main/java/org/apache/tinkerpop/gremlin/hadoop/structure/io/FileSystemStorage.java