jsp- How to send value to database table to process? - ajax

Question

I am new to AJAX and I have a JSP page that looks like below:
The new username column allows me to input any string of text and when I hit update user button,it should update the table in my database.
My table in database structure has a unique column AUSERNAME which stores the username as shown in the screenshot. After clicking the update button, it shall pass the new username value and update that field in table. This is what I am trying to achieve.
I know I have to make an AJAX call in my JSP page which looks like below:
<script >
function update(param) {
var currentbal = document.getElementsByName('NewUserName' + param)[0].value;
console.log(currentbal);
$.ajax({
type: "POST",
url: "update.jsp",
data: { name: currentbal},
success:function( msg ) {
alert( "Data Updated: " + msg );
},error: function (xhr, ajaxOptions, thrownError) {
alert(xhr.status);
alert(thrownError);
}
});
}
</script>
As for my update.jsp page, I am not too sure how to work on it and make the changes to the table. I believe I need to create a function in it but unsure how to pass the values to it and use sql statements to update it.

Answer 1

In your jsp page you can do something like this :
<%#page import= "java.sql.*" %>
<%#page import= "java.io.*" %>
<%
//getting data send from ajax request
String id= request.getParameter("id");
String user = request.getParameter("name"); //name for example
//data base code
try{
Class.forName("com.mysql.jdbc.Driver");
}
catch (ClassNotFoundException e) {
e.printStackTrace();
}
Connection con = null;
ResultSet resultSet = null;
Statement stmt = null;
int row=0;
try {
con=DriverManager.getConnection("jdbc:mysql://localhost:3306/abc","root","swati");
String sql = "UPDATE `tablename` SET `user`=? WHERE `id`=?"; //updating table
PreparedStatement statement = con.prepareStatement(sql);
statement.setString(1, name);
statement.setString(2, id);
row = statement.executeUpdate();
if (row > 0) {
String txt="updated";
// forwards to the message page
}
}
else {
String txt="not updated";
}
}
catch (Exception ex) {
ex.printStackTrace();
}
}
response.setContentType("text/plain");
response.setCharacterEncoding("UTF-8");
response.getWriter().write(txt);
%>
Hope this help you !