optimize the refund

src/main/java/com/ctrip/fun/golf/service/order/OpEventActivityOrderService.java

@@ -512,7 +512,9 @@ public class OpEventActivityOrderService
 			    String[] playerNumArray = playerNum.split(",");
                 List<Integer> players = new ArrayList<Integer>();
 			    if(playerNumArray.length == 0){
+			    	if(playerNum.trim() != null && !"".equals(playerNum)){
 			    		players.add(Integer.valueOf(playerNum.trim()));
+			    	}
 	            }else{
 	            	for (String playerNumStr : playerNumArray) {
 	            		if(playerNumStr.trim() != null && !"".equals(playerNumStr)){