建立预约网站的最简单方法是什么？

My wife is starting a new business and wants me to create a website for her that will allow clients to book appointments. I could obviously go ahead and start building something from scratch, but given that this is a fairly standard problem, I would prefer to reuse an existing solution (preferably in Java, but there is some flexibility on this) or build on top of a hosted solution like Google Calendar. What would you recommend?My wife is starting a new business and wants me