this problem may be very simple .

Now i am developing a library management system , using Linux + oracle8i as server ,and using java servlet to process difference user requests .

Now my supervisor ask me to implement a calendar function. That means after end-user select the year and month , i should display a calendar of month specified. and then when user select some day , and change its attribute( for example , change may 7th 2001 to holiday ), and click "submit" button , i should save the changes to database and show the changes on that calendart( like if it is aa holiday , add some star gif to mark it )

my questions is
1 which java class should i use to calculate weekdays( like monday/saturday/sunday )

2 i have written a html file to show calendar . i wonder when user click the "submit" button , how can i know which day user focus on ( i am not familiar with HTML , i use pair to show that calendar )

3 i think html + servlet will not work under this situation, and APPLET + SERVLET can do this job , am i right ?
(applet process user operation and display , using servlet to access database )

Help me Please