code: private static String getQTasteRoot() {
          String qtasteRoot = System.getenv("QTASTE_ROOT");
          if (qtasteRoot == null) {
              System.err.println("QTASTE_ROOT environment variable is not defined");
              System.exit(1);
          }
          try {
              qtasteRoot = new File(qtasteRoot).getCanonicalPath();
          } catch (IOException e) {
              System.err.println("QTASTE_ROOT environment variable is invalid (" + qtasteRoot + ")");
              System.exit(1);
          }
          return qtasteRoot;
      }
docs: Get QTaste root directory from QTASTE_ROOT environment variable.
  
  @return the QTaste root directory