Getting the data from SQL and inserting it inside the Java Textfield

I’ve been trying to get the data from the SQL and insert it inside the JTextfield.

Class.forName("com.mysql.cj.jdbc.Driver");
Connection connection =DriverManager.getConnection("jdbc:mysql://localhost:3306/Management", "root", "admin"); 
Statement st = connection.createStatement();
String sql ="SELECT * FROM information WHERE id =?";

pst=connection.prepareStatement(sql);
pst.setString(1,txtCustomerId.getText());
rs=pst.executeQuery();

if (rs.next()){
String ID = rs.getString("Firstname");
txtFirstname.setText(ID);
}

This code is in the button action, but when I clicked the button, there is nothing happening.

Answer

I redo my JFrame and rewrite this code. There is no problem with this code. I think it just override because I copied the previous JFrame.