code: private Grammar getEqualGrammar(Grammar gr) {
  
  		for (Grammar gx : this.grammars) {
  			if (gr == gx) {
  				// System.out.println("Exactly the same grammar found: " + gx);
  				return gx;
  			}
  
  			if (isSameGrammarType(gr, gx)) {
  				// type of grammar the same
  
  				if (gr.getNumberOfEvents() == gx.getNumberOfEvents()) {
  					List<Grammar> handled = new ArrayList<Grammar>();
  					if (isEqualGrammar(gr, gx, handled)) {
  						// the same grammar found
  						// System.out.println("Same grammar found for: " + gx +
  						// " == " + gr);
  						return gx;
  					}
  				}
  			}
  
  		}
  
  		return null;
  	}
docs: != null ... found equal grammar