Resources.getMessage takes 4 times as long as necessary because it calls the 
static function MessageFormat.format()

This function essentially instantiates a new MessageFormat object every time 
and then formats a message.  With each new instantiation, the message string 
must be parsed.

Using a profiling tool, I made 18,000 consecutive calls to the 
ResourceMessages.getMessage(String, Object[]) function on my machine which took 
49,340ms to process.  47,695ms was consumed in the MessageFormat.format() 
function.

I altered the class and created a static hashtable to cache MessageFormats 
after each initial request.  The formats were re-used instead of parsing the 
string with each call.  Making the same number of call to 
ResourceMessages.getMessage took only 10,086ms.

This is a simple alteration, below is the code I used to make this change.

    private static Hashtable formats = new Hashtable();
    private static MessageFormat getFormat(String name)
        throws MissingResourceException {
        MessageFormat format = (MessageFormat) formats.get(name);
        if (format==null) {
            format = new MessageFormat(rb.getString(name));
            formats.put(name, format);
        }
        return format;
    }

    /** Retrieves a message with arbitrarily many arguments. */
    public static String getMessage(String name, Object[] a)
	    throws MissingResourceException {
        Format f = getFormat(name);
        synchronized(f) {
            return f.format(a);
        }
    }