private Object executeStellar(String expression){
  Object result=null;
  try {
    result=executor.execute(expression);
  }
 catch (  Throwable t) {
    writeLine(ERROR_PROMPT + t.getMessage());
    t.printStackTrace();
  }
  return result;
}

private Object executeStellar ( String expression ) { Object result = null ; try { result = executor . execute ( expression ) ; } catch ( Throwable t ) { writeLine ( ERROR_PROMPT + t . getMessage ( ) ) ; t . printStackTrace ( ) ; } return result ; }
executes a stellar expression .
