public Builder addCommand(String command, int code, OnCommandResultListener onCommandResultListener) {
      return addCommand(new String[]{
          command
      }, code, onCommandResultListener);
    }
<p>Add a command to execute, with a callback to be called on completion</p>

<p>The thread on which the callback executes is dependent on various factors, see {@link Shell.Interactive}
for further details</p>

@param command
    Command to execute
@param code
    User-defined value passed back to the callback
@param onCommandResultListener
    Callback to be called on completion
@return This Builder object for method chaining
imitate/src/main/java/com/engineer/imitate/shell/Shell.java