public ContextLogger add(final String msg, final Object... params) {
        if (doLog) {
            if (params != null && params.length > 0) {
                message.append(String.format(msg, params));
            } else {
                message.append(msg);
            }

            message.append("(").append(System.currentTimeMillis() - startTime).append("ms);");
        }
        return this;
    }
Helper class to construct log messages. Optimized to log what is happening in a method,
but can be used in other situations as well.
<br>
All logging is done on level given in constructor, default is VERBOSE level.
main/src/main/java/cgeo/geocaching/utils/ContextLogger.java