Struts2 Jquery Grid
i have used Struts2 Jquery Grid and my grid is having some Rows in which there are some usernames , passwords and so on, if i am adding any duplicate username it is allowing me to add the duplicate username, i want to know if there is a way which will warn me that there is a user with the same username. 
Struts2 Jquery Grid
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i have used Struts2 Jquery Grid and my grid is having some Rows in which there are some usernames , passwords and so on, if i am adding any duplicate username it is allowing me to add the duplicate username, i want to know if there is a way which will warn me that there is a user with the same username. 