title: How to check if JPassword field is null
body: <p>I want to check the username and password in Swing. </p>
  
  <p>The check works for username, but it doesn't work for JPaswordfield. I am posting the related code:</p>
  
  <pre><code>//Here I get the password
  Char[] pwd = jt1.getPassword(); 
  String s = new String(pwd);  //converting char to string
  String p = s;
  
  //In the JButton checking username and password(Username check works fine but not passwordfield)
  
  jb.addActionListener(new ActionListener() {
                           public void actionPerformed(ActionEvent e)
                             {
                              if ((jt.getText().length()) == 0)
                              {
                                     JFrame jf1 = new JFrame("UserName");
                                           jf1.setSize(401, 401);
                                           //jf1.setVisible(true);
                                           jf1.setDefaultCloseOperation(jf1.EXIT_ON_CLOSE);
                                           JOptionPane.showMessageDialog(jf1, "User Name is empty");
                              }
  
                           else if((p.length()) == 0)
                              {
  
                                     JFrame jf1 = new JFrame("Password");
                                           jf1.setSize(401, 401);
                                           //jf1.setVisible(true);
                                           jf1.setDefaultCloseOperation(jf1.EXIT_ON_CLOSE);
                                           JOptionPane.showMessageDialog(jf1, "Password is empty");
                              }
  
                           else if ((p.length() == 0) &amp;&amp; (jt.getText().length()) == 0)
                              {
                                     JFrame jf1 = new JFrame("UserName and Password");
                                           jf1.setSize(401, 401);
                                           //jf1.setVisible(true);
                                           jf1.setDefaultCloseOperation(jf1.EXIT_ON_CLOSE);
                                           JOptionPane.showMessageDialog(jf1, "Username and Password is 
  empty");
                              }
  
                              else
                              { //go to another method}
  Can someone help
  </code></pre>