code: public Map<String, T> map(File[] files, int start, int count) {
  		final Map<String, T> results = new LinkedHashMap<>();
  		scan(files, start, count, new Consumer<File>() {
  			@Override
  			public void accept(File file) {
  				@Nullable Tuple2<String, T> mapping = file2map(file);
  				if (mapping != null) {
  					String key = mapping.get0();
  					results.put(key, results.containsKey(key)
  						? duplicate2map(results.get(key), mapping.get1())
  						: mapping.get1());
  				}
  			}
  		});
  		return results;
  	}
docs: /* map