static  class ComparatorPinYin implements Comparator<ByOperationBillItem>{  
        @Override  
        public int compare(ByOperationBillItem o1, ByOperationBillItem o2) { 
            return ToPinYinString(o1.getItemName()).compareTo(ToPinYinString(o2.getItemName()));  
        }  
        private String ToPinYinString(String str){  
            StringBuilder sb=new StringBuilder();  
            String[] arr=null;  
            for(int i=0;i<str.length();i++){  
                arr= PinyinHelper.toHanyuPinyinStringArray(str.charAt(i));  
                if(arr!=null && arr.length>0){  
                    for (String string : arr) {  
                        sb.append(string);  
                    }  
                }  
            }  
            return sb.toString();  
        }  
    }