How To: String --> sql.Date and String --> java.util.Date

I posted below to java101 group and got no respond.  Thought I try it here.

 

I've a jsp that contains a text input field that represent a date. This date is 
map to a Date field in a table. 

I'm using Struts to control the application flow. When user press submit, the 
ActionForm takes over and basically call the Validate Action class and Form 
Action that uses beancopy to copy data to a DAO class. In this DAO class, I 
declare the date field as sql.Date.

Can somebody show me how should I handle the following:

1) In the Validation action, I need to check the input Date field (String 
class) to make sure that it is greater than today's date. How should I do this?

2) In the bean copy or my DAO, how should I convert this String to sql.Date?

Thanks.