content: package java_cup;
  
  import java_cup.assoc;
  import java.util.Hashtable;
  import java.util.Enumeration;
  
  /** This class represents a terminal symbol in the grammar.  Each terminal 
   *  has a textual name, an index, and a string which indicates the type of 
   *  object it will be implemented with at runtime (i.e. the class of object 
   *  that will be returned by the scanner and pushed on the parse stack to 
   *  represent it). 
   *
   * @version last updated: 7/3/96
   * @author  Frank Flannery
   */
  public class terminal extends symbol {
  
    /*-----------------------------------------------------------*/
    /*--- Constructor(s) ----------------------------------------*/
    /*-----------------------------------------------------------*/
  
    /** Full constructor.
     * @param nm the name of the terminal.
     * @param tp the type of the terminal.
     */
    public terminal(String nm, String tp, int precedence_side, int precedence_num) 
      {
        /* superclass does most of the work */
        super(nm, tp);
  
        /* add to set of all terminals and check for duplicates */
        Object conflict = _all.put(nm,this);
        if (conflict != null)
  	// can't throw an execption here because this is used in static 
  	// initializers, so we do a crash instead
  	// was:
  	// throw new internal_error("Duplicate terminal (" + nm + ") created");
  	(new internal_error("Duplicate terminal (" + nm + ") created")).crash();
  
        /* assign a unique index */
        _index = next_index++;
  
        /* set the precedence */
        _precedence_num = precedence_num;
        _precedence_side = precedence_side;
  
        /* add to by_index set */
        _all_by_index.put(new Integer(_index), this);
      }
  
    /*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .*/
  
    /** Constructor for non-precedented terminal
      */ 
  
    public terminal(String nm, String tp) 
      {
        this(nm, tp, assoc.no_prec, -1);
      }
  
    /*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .*/
  
    /** Constructor with default type. 
     * @param nm the name of the terminal.
     */
    public terminal(String nm) 
      {
        this(nm, null);
      }
  
    /*-----------------------------------------------------------*/
    /*-------------------  Class Variables  ---------------------*/
    /*-----------------------------------------------------------*/
  
    private int _precedence_num;
    private int _precedence_side;
  
    /*-----------------------------------------------------------*/
    /*--- (Access to) Static (Class) Variables ------------------*/
    /*-----------------------------------------------------------*/
  
    /** Table of all terminals.  Elements are stored using name strings as 
     *  the key 
     */
    protected static Hashtable _all = new Hashtable();
  
    //Hm Added clear  to clear all static fields
    public static void clear() {
        _all.clear();
        _all_by_index.clear();
        next_index=0;
        EOF = new terminal("EOF");
        error = new terminal ("error");
    }
    
    /** Access to all terminals. */
    public static Enumeration all() {return _all.elements();}
  
    /** Lookup a terminal by name string. */ 
    public static terminal find(String with_name)
      {
        if (with_name == null)
  	return null;
        else 
  	return (terminal)_all.get(with_name);
      }
  
  
    /*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .*/
  
    /** Table of all terminals indexed by their index number. */
    protected static Hashtable _all_by_index = new Hashtable();
  
    /** Lookup a terminal by index. */
    public static terminal find(int indx)
      {
        Integer the_indx = new Integer(indx);
  
        return (terminal)_all_by_index.get(the_indx);
      }
  
    /*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .*/
  
    /** Total number of terminals. */
    public static int number() {return _all.size();}
  
    /*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .*/
   
    /** Static counter to assign unique index. */
    protected static int next_index = 0;
  
    /*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .*/
  
    /** Special terminal for end of input. */
    public static terminal EOF = new terminal("EOF");
  
    /*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .*/
  
    /** special terminal used for error recovery */
    public static terminal error = new terminal("error");
  
    /*-----------------------------------------------------------*/
    /*--- General Methods ---------------------------------------*/
    /*-----------------------------------------------------------*/
  
    /** Report this symbol as not being a non-terminal. */
    public boolean is_non_term() 
      {
        return false;
      }
  
    /*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .*/
  
    /** Convert to a string. */
    public String toString()
      {
        return super.toString() + "[" + index() + "]";
      }
  
    /*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .*/
  
    /** get the precedence of a terminal */
    public int precedence_num() {
      return _precedence_num;
    }
    public int precedence_side() {
      return _precedence_side;
    }
  
    /** set the precedence of a terminal */
    public void set_precedence(int p, int new_prec) {
      _precedence_side = p;
      _precedence_num = new_prec;
    }
  
    /*-----------------------------------------------------------*/
  
  }
  