Replacing contents inside curly braces (for e.g. {1}) with something else [duplicate]

Question

I have a string as follows

Hey {1}, you are {2}.

Here 1 and 2 are key whose value will be added dynamically.

Now I need to replace {1} with the value that 1 represents and then I need to replace {2} with the value that 2 represents in the sentence above.

How do I do it?

I know what split function of a string does and I know very well that with that function I can do what I want but I am looking for something better.

Note: I don't know what these keys are in advance. I need to retrieve the keys as well. And then according to the keys I need to replace the values in the string.

Answer 1

You can use MessageFormat from java.text.MessageFormat. Message Format has some example on how it can be used in this type of scenario

Answer 2

Thanks to https://stackoverflow.com/users/548225/anubhava for this one.. :). You could do something like this:

public static void main(String[] args) {
    String s = "Hey {1}, you are {2}.";
    HashMap<Integer, String> hm = new HashMap();
    hm.put(1, "one");
    hm.put(2, "two");
    Pattern p = Pattern.compile("(\\{\\d+\\})");
    Matcher m = p.matcher(s);
    while (m.find()) {
        System.out.println(m.group());
        String val1 = m.group().replace("{", "").replace("}", "");
        System.out.println(val1);
        s = (s.replace(m.group(), hm.get(Integer.parseInt(val1))));
        System.out.println(s);
    }

}

Output:

Hey one, you are two.