Concatenate the specified character at the end of a number in a string

 

I'm working on a project for the hospital , The doctor asked that all the units at the end of the number be spliced , such as "(4)9*&5MM）8999）3&4*9*[email protected]" The numbers in this string of words are spliced with a unit at the end , become (4°)9°*&5°MM）8999°）3°&4°*9°*2°@, My code is shown in the figure below ：

 code snippet ：
/**
 *  Number end splice ° Symbol 
 */
public static String appendDegreeMark(String content) {
    int lastEndIndex = 0;
    Matcher matcher = pattern.matcher(content);
    StringBuilder stringBuilder = new StringBuilder();
    while (matcher.find()) {
        int startIndex = matcher.start(0);
        if (lastEndIndex != startIndex) {
            String preContent = content.substring(lastEndIndex, startIndex);
            stringBuilder.append(preContent); // Splices non numeric text between the end of the last number and the start of the current matching number 
        }
        stringBuilder.append(matcher.group(0)).append("°");// Splice units 
        lastEndIndex = matcher.end(0);// Starting position of the next round 
    }
    // If the starting position of the next round is equal to the length of the text, it means that all the text has been spliced , Otherwise, splice the remaining text  
    if (lastEndIndex < content.length()) {
        String lastStr = content.substring(lastEndIndex ,content.length());
        stringBuilder.append(lastStr);
    }
    return stringBuilder.toString();
}