Java实现占位符名称替换值

2024-04-02 19:55

短信预约 -IT技能 免费直播动态提醒

前言

占位符现在应该说是比较流行的动态赋值，方法有String.format()，通过%s或其他来赋值；或者MessageFormat.format()，通过{0}来赋值，参数名都不可定义

项目中有个需求，根据一串带着参数名占位符的url，替换掉对应参数名的值，由此有了以下的工具类。

代码


import java.util.Map;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

public class StringFormatUtil {

    private static final Pattern pattern = Pattern.compile("\\{(.*?)\\}");
    private static Matcher matcher;

    private StringFormatUtil(){}


    
    public static String format(String sourStr, Map<String, Object> param) {
        String tagerStr = sourStr;
        if (param == null)
            return tagerStr;
        try {
            matcher = pattern.matcher(tagerStr);
            while (matcher.find()) {
                String key = matcher.group();
                String keyclone = key.substring(1, key.length() - 1).trim();
                Object value = param.get(keyclone);
                if (value != null)
                    tagerStr = tagerStr.replace(key, value.toString());
            }
        }catch (Exception e){
            return null;
        }
        return tagerStr;
    }

    //public static void main(String[] args) {
    //    String url = "https://xxx.com/cfes?c={campaign_name}&af_siteid={af_siteid}&clickid={clickid}&android_id={android_id}&advertising_id={advertising_id}&idfa={idfa}";
    //    Map<String, Object> map = new LinkedHashMap<>();
    //    map.put("campaign_name", "111");
    //    map.put("af_siteid", "222");
    //    map.put("clickid", "333");
    //    map.put("android_id", "444");
    //    map.put("advertising_id", "555");
    //    map.put("idfa", "");
    //    System.out.println(format(url, map));
    //}
}