tools/dasm/src/java_cup/parse_reduce_table.java

package java_cup;


/** This class represents the complete "reduce-goto" table of the parser.
 *  It has one row for each state in the parse machines, and a column for
 *  each terminal symbol.  Each entry contains a state number to shift to
 *  as the last step of a reduce. 
 *
 * @see     java_cup.parse_reduce_row
 * @version last updated: 11/25/95
 * @author  Scott Hudson
 */
public class parse_reduce_table {
 
  /*-----------------------------------------------------------*/
  /*--- Constructor(s) ----------------------------------------*/
  /*-----------------------------------------------------------*/

  /** Simple constructor.  Note: all terminals, non-terminals, and productions 
   *  must already have been entered, and the viable prefix recognizer should
   *  have been constructed before this is called.
   */
  public parse_reduce_table()
    {
      /* determine how many states we are working with */
      _num_states = lalr_state.number();

      /* allocate the array and fill it in with empty rows */
      under_state = new parse_reduce_row[_num_states];
      for (int i=0; i<_num_states; i++)
    under_state[i] = new parse_reduce_row();
    }

   
  /*-----------------------------------------------------------*/
  /*--- (Access to) Instance Variables ------------------------*/
  /*-----------------------------------------------------------*/

  /** How many rows/states in the machine/table. */
  protected int _num_states;

  /** How many rows/states in the machine/table. */
  public int num_states() {return _num_states;}

  /*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .*/

  /** Actual array of rows, one per state */
  public  parse_reduce_row[] under_state;
 
  /*-----------------------------------------------------------*/
  /*--- General Methods ---------------------------------------*/
  /*-----------------------------------------------------------*/

  /** Convert to a string. */
  public String toString()
    {
      String result;
      lalr_state goto_st;
      int cnt;

      result = "-------- REDUCE_TABLE --------\n";
      for (int row = 0; row < num_states(); row++)
    {
      result += "From state #" + row + "\n";
      cnt = 0;
      for (int col = 0; col < under_state[row].size(); col++)
        {
          /* pull out the table entry */
          goto_st = under_state[row].under_non_term[col];

          /* if it has action in it, print it */
          if (goto_st != null)
        {
          result += col + ":"; 
          result += goto_st.index();

          /* end the line after the 3rd one */
          cnt++;
          if (cnt == 3)
            {
              result += "\n";
              cnt = 0;
            }
        }
        }
          /* finish the line if we haven't just done that */
      if (cnt != 0) result += "\n";
    }
      result += "-----------------------------";

      return result;
    }

  /*-----------------------------------------------------------*/

};