Why do I get a "java.lang.NoSuchMethodError"?

Question

Hello!
I going to send a mail with a socketconnection, the program worked when I not was using GUI. Now I'm trying to make a GUI-version BUT it's not working. There is no problem to compile the program but when I am running the program I get a "java.lang.NoSuchMethodError"...why?
I'v not been programming to much so I would really appreciate some tips!
Some namings are in swedish! Sorry for that!
Thank you for helping me// MM
import java.awt.*;
import java.awt.event.*;
import java.io.*;
import java.net.*;
import java.util.*;
import javax.swing.*;
public class Lab3 {
Window frame;
public void main(String args[]) throws Exception{
     frame=new Window();
     Maila mail     =new Maila(args);
     String file=mail.hittaFil(args);
     mail.maila(file);
class Window extends JFrame implements ActionListener{
     public JFrame mailFrame;
     public JPanel mailPanel;
     public JTextArea mailMedd;
     public JTextField adressField, filNamnField, mailAdressField, meddelandeField;
     public JLabel webbAdressLabel, filNamnLabel, mailAdressLabel, meddelandeLabel, blankLabel, svarLabel;
     public JButton searchButton, sendButton;
public Window() {
     mailFrame = new JFrame("Finn och skicka fil");
     mailFrame.setSize(80, 150);
     mailPanel = new JPanel();
     // Add the widgets.
     addWidgets();
     // Add the panel to the frame.
     // Exit when the window is closed.
mailFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
     // Show the frame
     mailFrame.pack();
     mailFrame.setVisible(true);
// Create and add the widgets for frame
private void addWidgets() {
     // Create widgets.
     mailMedd = new JTextArea(6,3);
     adressField = new JTextField(30);
     filNamnField = new JTextField(30);
     mailAdressField = new JTextField(30);
     meddelandeField = new JTextField(30);
     webbAdressLabel = new JLabel("Webb-Adress: ", SwingConstants.RIGHT);
     filNamnLabel = new JLabel(" Filnamn: ", SwingConstants.RIGHT);
     blankLabel = new JLabel("", SwingConstants.RIGHT);
     meddelandeLabel = new JLabel(" Meddelande:", SwingConstants.RIGHT);
     svarLabel = new JLabel(" ");
     mailAdressLabel = new JLabel(" Skicka till: ", SwingConstants.RIGHT);
     searchButton = new JButton("Search for file");
     sendButton = new JButton("Send mail");
     // Listen to events from buttons.
     searchButton.addActionListener(this);
     sendButton.addActionListener(this);
     // Add widgets to container.
     Box b1h1 = Box.createHorizontalBox();
     Box b1h2 = Box.createHorizontalBox();
     Box b1h3 = Box.createHorizontalBox();
     Box b1h4 = Box.createHorizontalBox();
     Box b1h5 = Box.createHorizontalBox();
     Box b1h6 = Box.createHorizontalBox();
     Box b1h7 = Box.createHorizontalBox();
     Box bv = Box.createVerticalBox();
     b1h1.add(webbAdressLabel);
     b1h1.add(adressField);
     b1h2.add(filNamnLabel);
     b1h2.add(filNamnField);
     b1h3.add(blankLabel);
     b1h3.add(searchButton);
     b1h6.add(mailAdressLabel);
     b1h6.add(mailAdressField);
     b1h7.add(blankLabel);
     b1h7.add(sendButton);
     b1h4.add(meddelandeLabel);
     b1h4.add(blankLabel);
     b1h5.add(blankLabel);
     b1h5.add(svarLabel);
     bv.add(Box.createVerticalStrut(15));     
     bv.add(b1h1);
     bv.add(Box.createVerticalStrut(3));
     bv.add(b1h2);
     bv.add(Box.createVerticalStrut(15));
     bv.add(b1h3);
     bv.add(Box.createVerticalStrut(25));
     bv.add(b1h4);
     bv.add(Box.createVerticalStrut(15));
     bv.add(mailMedd);
     bv.add(Box.createVerticalStrut(3));
     bv.add(b1h5);
     bv.add(Box.createVerticalStrut(30));
     bv.add(b1h6);
     bv.add(Box.createVerticalStrut(15));
     bv.add(b1h7);
     bv.add(Box.createVerticalStrut(3));
     mailFrame.getContentPane().add(bv, BorderLayout.CENTER);
// Implementation of ActionListener interface.
public void actionPerformed(ActionEvent event) {
class Maila{
String[] args;
public Maila(String[] args){
     this.args=args;
     public void maila(String file) throws IOException{
     Socket mailSocket;
     int j=0;
     String from,till,kopia,avsandare,mottagare;
     Vector to = new Vector();
     String subject;
     String data;
     BufferedReader in=new BufferedReader(new InputStreamReader(System.in));
     PrintWriter out;
     BufferedReader mailIn;
     System.out.print("Fr?n: ");
     from=in.readLine();
     System.out.print("Till: ");
     till = in.readLine();
     //System.out.print("Skickakopia till: ");
     //kopia=in.readLine();
     //System.out.print("Avs?ndare: ");
     //avsandare=in.readLine();
     //System.out.print("Mottagare:: ");
     //mottagare=in.readLine();
     StringTokenizer st = new StringTokenizer(till);
     int nr = st.countTokens();
     while(st.hasMoreTokens()){
     nr = st.countTokens();
     to.add(st.nextToken());
     nr = st.countTokens();
     System.out.print("?mne: ");
     subject = in.readLine();
     System.out.println();
     System.out.println("Skriv ditt meddelande. Avsluta med 'Enter'");
     data = in.readLine();
     for(int k=0; k<to.size(); k++){
     String tillfadress = (String)to.elementAt(k);
     Object localhost = InetAddress.getLocalHost();
     mailSocket=new Socket("localhost",25);
     out=new PrintWriter(mailSocket.getOutputStream(), true);     
     mailIn=new BufferedReader(new InputStreamReader(mailSocket.getInputStream()));
     out.println("HELO "+"localhost");
     out.println("MAIL FROM: " + from);
     out.println("RCPT TO: " + tillfadress);
     out.println("DATA");
out.println("Subject:" + subject);
     out.println("From: " + from);
     out.println("To: " + tillfadress);
     out.println("CC: " + tillfadress);
     out.println(data+file);
     out.println(".");
//     System.out.println(mailIn.readLine() + "8");
     //out.flush();
     //printer.println("Subject: " + subject);
     //printer.println("From: " + sender);
     //printer.println("To: " + recipient);
     //printer.println("CC: " + cc);
     //printer.println(data);
public String hittaFil(String[] args){
     int i;
     InputStream in = null;
     OutputStream out = null;
     String text=null;
     try{
     URL url = new URL("http://"+args[0]);
     for(i=2;i<args.length;i++){
          try{
          URL urlx = new URL(url,"~"+args);
          in = urlx.openStream();
          BufferedReader indata = new BufferedReader(new InputStreamReader(in));
          text = indata.readLine();
          catch(FileNotFoundException e){
          System.out.println("Ingen fil med givet namn hittad!");
     catch(Exception e){
     System.err.println(e);
     System.err.println("Usage: java GetURL <URL> <filename>");
     finally{
     try{
          in.close();
          out.close();
     catch(Exception e){}
     return(text);

Answer 1

I don't see a main method in your code. The one declared in your Lab3.java is not static.