TokenReplacement.java

public class TokenReplacement {

    private static final Logger log =
            LoggerFactory.getLogger(TokenReplacement.class);

    private static final Pattern TOKEN_PATTERN = Pattern.compile("\\$\\{(.*?)\\}");

    public static String replaceTokens(final String input, Properties props) {

        Matcher matcher = TOKEN_PATTERN.matcher(input);

        StringBuilder output = new StringBuilder();
        while (matcher.find()) {

            if (log.isDebugEnabled()) {
                log.debug("Found the text \"{}\" starting at " +
                        "index {} and ending at index {}",
                        new Object[]{matcher.group(), matcher.start(), matcher.end()});
            }

            matcher.appendReplacement(output, props.getProperty(matcher.group(1)));
        }
        matcher.appendTail(output);

        return output.toString();
    }

}