What is the equivalent of Regex-replace-with-function-evaluation in Java 7?

Question

I\'m looking for a very simple way of getting the equivalent of something like the following JavaScript code. That is, for each match I would like to call a certain

Answer 1

When allowing Java 8 you can use Lambda-Expressions, to have a JavaScript like replace:

String result = StringReplacer.replace("Hello World!", Pattern.compile("\\S+"), m -> ("" + m.group().length()));

StringReplacer.java:

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

public class StringReplacer {
    public static String replace(String input, Pattern regex, Function callback) {
        StringBuffer resultString = new StringBuffer();
        Matcher regexMatcher = regex.matcher(input);
        while (regexMatcher.find()) {
            regexMatcher.appendReplacement(resultString, callback.apply(regexMatcher));
        }
        regexMatcher.appendTail(resultString);

        return resultString.toString();
    }
}

Source: http://www.whitebyte.info/programming/string-replace-with-callback-in-java-like-in-javascript