random password generator

Question

hi friends,,

i am developing one web site in this i have one problem that is if i forget my password the system will regenerate password and that password will send to my mail id,and that will be updates in database also please do any one in 3-tier architecture please...


if i click forget password field, that will generate one email text field in that i will enter my email id and click on generate button and new password will be generated and again that will be send to email and that will be updated in database also..in database only two fields have,one is username and password...so the password field will be updated...

how please do any one ,,,in 3-tier


please give me the source code for this one.....please...please