if statement not executed in JSP scriptlet - mysql

Question

i encountered the following problem. I have made a table in mysql named 'users' and i want to add users using JSP. The primary key is the Email and i want to check before adding another user if the email already exists. If the email already exists the users will not be added to the database and a message "email already exists" will appear.
I created ResultSet rs object and extracted the "Email" column into a String email using a while loop.Now, here comes the problem. Suppose i have a user with the "denis#yahoo.com" email. If i try to add an user with the exact same email an error will occur which means my if statement was ignored. I looked up in the debug mode for the variables email and Email and they had the exact same "denis#yahoo.com" and still the if statement was ignored.
<!-- file name: addUser.jsp -->
<%
String Email=request.getParameter("Email");
String Name = request.getParameter("Name");
String Adress = request.getParameter("Adress");
String Phone = request.getParameter("Phone");
if (Email != null)
{
jb.connect(); // connect to the database using JavaBean class
ResultSet rs;
rs=jb.seeTable("users");// rs gets first row of table
String email;
int a=1;
while(rs.next())
{
email=rs.getString("Email");
if(Email==email)
{
a=0;
jb.disconnect();
%>
<p> The email already exists</p>
<%
break;
}
}
if(a==1){
jb.addUser(Email,Name, Adress, Phone);
jb.disconnect();
%>
<p>Data has been added.</p>
<%
}
} else {
%>
<form action="addUser.jsp" >
Email: <input type="text" name="Email"><br>
Name: <input type="text" name="Name"><br>
Adress: <input type="text" name="Adress"><br>
Phone: <input type="text" name="Phone"><br>
<button type="submit" >Add User</button><br>
</form>
<%
}
%>
I use NetBeans IDE 8.2, and something that i think is odd appeared in the debug mode. One of the email i try to test appeared with bold characters meanwhile the other was not bold.
Why is my if statement ignored if i add an user with the exact same email of another? Please help me out!