How to validate an email from JTextField

java, joptionpane, jtextfield, swing, validation

Solution

If you're trying to validate an email, use `String.matches(regex)`

Here is an imlementation of the email regex validation patter from this site. An explanation of the regex can also be found on the site.

private static final String EMAIL_PATTERN = 
    "^[_A-Za-z0-9-\\+]+(\\.[_A-Za-z0-9-]+)*@"
    + "[A-Za-z0-9-]+(\\.[A-Za-z0-9]+)*(\\.[A-Za-z]{2,})$";

if (!email.matches(EMAIL_PATTERN)) {}

Problem

Just like the title says, I want to display a jOptionPane if there's a missing specific character in a jTextField. Let's say that character is "@". I tried something like this: ``` private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) { String email = (String)txtEmail.getText(); if (!email.equals(email) && email.equals("@")){ jOptionPane1.showMessageDialog(null, "Please"); } } ``` However, I can't get this to work. I also tried using `contains()` and `contentEquals()` but I don't know how to use it properly so I had changed the code. Searching on Google also doesn't help because I can't find what I want. Please consider helping. BTW, I'm using netbeans.

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