Java利用正则表达式统计某个字符串出现的次数

//统计某个字符出现的次数  

    private void countSubString(){  

        String string1="香蕉、玉米、面粉";  

        String string2="香蕉、玉米、面粉";  

        String string3="牛奶、鸡蛋";  

        StringBuffer stringBuffer=new StringBuffer();  

        stringBuffer.append(string1).append("、").append(string2).append("、").append(string3).append("、");  

        String totalString=stringBuffer.toString();  

        System.out.println("组拼后的字符串为:"+totalString);  

          

        while (totalString.length()>0) {  

            //得到第一个字符串比如"香蕉、"  

            int index=totalString.indexOf("、");  

            String foodName=totalString.substring(0,index+1);  

              

            Pattern pattern = Pattern.compile(foodName);    

            Matcher matcher = pattern.matcher(totalString);    

            int count=0;  

            while(matcher.find()){  

                count++;  

            }  

            totalString= totalString.replaceAll(foodName, "");  

            System.out.println("食品名字为:"+foodName+",出现次数为:"+count);  

            System.out.println("统计删除后字符串为:totalString="+totalString);  

            System.out.println("===============================");  

        }  

    }