import java.util.HashMap;

import java.util.Map;

import java.util.regex.*;

public class Main {

public static void main(String[] args) {

Map<String,String> map = new HashMap<>();

map.put("name", "Bob");

map.put("lang", "Java");

String s = "Hello, ${name}! You are learning ${lang}!";

System.out.println(replaceModule1(s,map));

}

static String replaceModule1(String ori,Map<String,String> map) {

var sb = new StringBuilder();

Pattern p = Pattern.compile("\\$\\{(\\w+)\\}");

Matcher m=p.matcher(ori);

while(m.find()) {

m.appendReplacement(sb, map.get(m.group(1)));

}

m.appendTail(sb);

return sb.toString();

}

}