提取一堆字符串中连在一起的数字，没有连在一起的则隔开

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public static List<String> getFullNumFromString(String str){         List<String> resultList = new ArrayList<>();         StringBuilder numBuilder = new StringBuilder();         str = str.replaceAll(" ","");         for (int i = 0; i < str.length(); i++) {             char ch = str.charAt(i);             if (ch >= 48 && ch <= 57) {                 numBuilder.append(ch);                 if ( i == str.length() -1) {                     resultList.add(numBuilder.toString());                 }             } else {                 if (!numBuilder.toString().equals("") && numBuilder.length() > 0) {                     resultList.add(numBuilder.toString());                     numBuilder = new StringBuilder();                 }             }         }         return resultList;     }