public void arrowLeft() {
    if (cursorPosition == 0) {
      return;
    }

    cursorPosition -= 1;
    inputModeScreenView.showInput(message, inputString.toString(), cursorPosition);
    inputModeScreenView.refreshTerminal();
  }
The presentation logic for the input mode.
hbase-hbtop/src/main/java/org/apache/hadoop/hbase/hbtop/screen/top/InputModeScreenPresenter.java