*** QueryParser.jj.org	Tue Jan 20 13:30:23 2004
--- QueryParser.jj	Thu Jan 22 08:47:43 2004
***************
*** 239,245 ****
  
      // If this term is introduced by AND, make the preceding term required,
      // unless it's already prohibited
!     if (conj == CONJ_AND) {
        BooleanClause c = (BooleanClause) clauses.elementAt(clauses.size()-1);
        if (!c.prohibited)
          c.required = true;
--- 239,246 ----
  
      // If this term is introduced by AND, make the preceding term required,
      // unless it's already prohibited
!     if (conj == CONJ_AND &&
! 	clauses.size() > 0 ) { // might be false if stop words are used...
        BooleanClause c = (BooleanClause) clauses.elementAt(clauses.size()-1);
        if (!c.prohibited)
          c.required = true;
***************
*** 250,258 ****
        // unless it's prohibited (that means we leave -a OR b but +a OR b-->a OR b)
        // notice if the input is a OR b, first term is parsed as required; without
        // this modification a OR b would parsed as +a OR b
!       BooleanClause c = (BooleanClause) clauses.elementAt(clauses.size()-1);
!       if (!c.prohibited)
!         c.required = false;
      }
  
      // We might have been passed a null query; the term might have been
--- 251,261 ----
        // unless it's prohibited (that means we leave -a OR b but +a OR b-->a OR b)
        // notice if the input is a OR b, first term is parsed as required; without
        // this modification a OR b would parsed as +a OR b
!       if ( clauses.size() > 0 ) { // might be false if stop words are used...
! 	BooleanClause c = (BooleanClause) clauses.elementAt(clauses.size()-1);
!         if (!c.prohibited)
!           c.required = false;
!       }
      }
  
      // We might have been passed a null query; the term might have been
***************
*** 363,371 ****
    protected Query getBooleanQuery(Vector clauses) throws ParseException
    {
      BooleanQuery query = new BooleanQuery();
      for (int i = 0; i < clauses.size(); i++) {
! 	query.add((BooleanClause)clauses.elementAt(i));
      }
      return query;
    }
  
--- 366,380 ----
    protected Query getBooleanQuery(Vector clauses) throws ParseException
    {
      BooleanQuery query = new BooleanQuery();
+     boolean empty = true;
      for (int i = 0; i < clauses.size(); i++) {
! 	BooleanClause clause = (BooleanClause)clauses.elementAt(i);
! 	if ( !clause.prohibited )
! 	    empty = false;
! 	query.add(clause);
      }
+     if ( empty )
+ 	return null;
      return query;
    }