import jregex.*;
import java.awt.*;
import java.applet.*;
import java.awt.event.*;

/*
* Simple email validator
*/
public class Email extends Applet{
   private static final String userNameChars="[\\w.\\-]+"; //letters, dots, hyphens
   private static final String alphaNums="\\w+";
   private static final String dot="\\.";
   private static final Pattern email=
      new Pattern(userNameChars + "@" + "(?:"+ alphaNums + dot + ")*" + alphaNums);
   
   Label lAddr=new Label("Type an address here:");
   TextField addrInput=new TextField(35);
   Label lResult=new Label("Result:");
   TextField display=new TextField(10);
   Button bCheck=new Button("Check");
   
   public void init(){
      GridBagLayout gb=new GridBagLayout();
      setLayout(gb);
      GridBagConstraints gbc=new GridBagConstraints();
      gbc.fill=gbc.BOTH;
      gbc.insets=new Insets(2,4,2,4);
      gbc.weightx=1;
      gbc.weighty=1;
      
      //gbc.gridwidth=gbc.RELATIVE;
      gbc.gridwidth=gbc.REMAINDER;
      gb.setConstraints(lAddr,gbc);
      add(lAddr);
      gb.setConstraints(addrInput,gbc);
      add(addrInput);
      
      gbc.gridwidth=1;
      gb.setConstraints(lResult,gbc);
      add(lResult);
      gb.setConstraints(display,gbc);
      add(display);
      
      gbc.gridwidth=gbc.REMAINDER;
      gb.setConstraints(bCheck,gbc);
      add(bCheck);
      
      display.setEditable(false);
      
      addrInput.addTextListener(new TextListener(){
         public void textValueChanged(TextEvent e){
            display.setText(null);
         }
      });
      
      bCheck.addActionListener(new ActionListener(){
         public void actionPerformed(ActionEvent e){
            display.setText(check(addrInput.getText())? "Valid": "Invalid");
         }
      });
   }
   
   private static boolean check(String s){
      return email.matcher(s).matches();
   }
}