I can't compile the JavaMail demo

Question

Can somebody please help me out. I am trying to compile one of the demos in JavaMail. It compiles successfully but it won't execute. It keeps giving me the normal exception when there is no 'main()' in a code. The code is below:
import java.util.*;
import java.io.*;
import javax.mail.*;
import javax.mail.event.*;
import javax.mail.internet.*;
import javax.activation.*;
* Demo app that exercises the Message interfaces.
* Show information about and contents of messages.
* @author John Mani
* @author Bill Shannon
public class msgshow {
static String protocol;
static String host = null;
static String user = null;
static String password = null;
static String mbox = null;
static String url = null;
static int port = -1;
static boolean verbose = false;
static boolean debug = false;
static boolean showStructure = false;
static boolean showMessage = false;
static boolean showAlert = false;
static boolean saveAttachments = false;
static int attnum = 1;
public static void main(String argv[]) {
     int msgnum = -1;
     int optind;
     InputStream msgStream = System.in;
     for (optind = 0; optind < argv.length; optind++) {
     if (argv[optind].equals("-T")) {
          protocol = argv[++optind];
     } else if (argv[optind].equals("-H")) {
          host = argv[++optind];
     } else if (argv[optind].equals("-U")) {
          user = argv[++optind];
     } else if (argv[optind].equals("-P")) {
          password = argv[++optind];
     } else if (argv[optind].equals("-v")) {
          verbose = true;
     } else if (argv[optind].equals("-D")) {
          debug = true;
     } else if (argv[optind].equals("-f")) {
          mbox = argv[++optind];
     } else if (argv[optind].equals("-L")) {
          url = argv[++optind];
     } else if (argv[optind].equals("-p")) {
          port = Integer.parseInt(argv[++optind]);
     } else if (argv[optind].equals("-s")) {
          showStructure = true;
     } else if (argv[optind].equals("-S")) {
          saveAttachments = true;
     } else if (argv[optind].equals("-m")) {
          showMessage = true;
     } else if (argv[optind].equals("-a")) {
          showAlert = true;
     } else if (argv[optind].equals("--")) {
          optind++;
          break;
     } else if (argv[optind].startsWith("-")) {
          System.out.println(
"Usage: msgshow [-L url] [-T protocol] [-H host] [-p port] [-U user]");
          System.out.println(
"\t[-P password] [-f mailbox] [msgnum] [-v] [-D] [-s] [-S] [-a]");
          System.out.println(
"or msgshow -m [-v] [-D] [-s] [-S] [-f msg-file]");
          System.exit(1);
     } else {
          break;
try {
     if (optind < argv.length)
     msgnum = Integer.parseInt(argv[optind]);
     // Get a Properties object
     Properties props = System.getProperties();
     // Get a Session object
     Session session = Session.getInstance(props, null);
     session.setDebug(debug);
     if (showMessage) {
          MimeMessage msg;
          if (mbox != null)
          msg = new MimeMessage(session,
               new BufferedInputStream(new FileInputStream(mbox)));
          else
          msg = new MimeMessage(session, msgStream);
          dumpPart(msg);
          System.exit(0);
     // Get a Store object
     Store store = null;
     if (url != null) {
          URLName urln = new URLName(url);
          store = session.getStore(urln);
          if (showAlert) {
          store.addStoreListener(new StoreListener() {
               public void notification(StoreEvent e) {
               String s;
               if (e.getMessageType() == StoreEvent.ALERT)
                    s = "ALERT: ";
               else
                    s = "NOTICE: ";
               System.out.println(s + e.getMessage());
          store.connect();
     } else {
          if (protocol != null)          
          store = session.getStore(protocol);
          else
          store = session.getStore();
          // Connect
          if (host != null || user != null || password != null)
          store.connect(host, port, user, password);
          else
          store.connect();
     // Open the Folder
     Folder folder = store.getDefaultFolder();
     if (folder == null) {
     System.out.println("No default folder");
     System.exit(1);
     if (mbox == null)
          mbox = "INBOX";
     folder = folder.getFolder(mbox);
     if (folder == null) {
     System.out.println("Invalid folder");
     System.exit(1);
     // try to open read/write and if that fails try read-only
     try {
          folder.open(Folder.READ_WRITE);
     } catch (MessagingException ex) {
          folder.open(Folder.READ_ONLY);
     int totalMessages = folder.getMessageCount();
     if (totalMessages == 0) {
          System.out.println("Empty folder");
          folder.close(false);
          store.close();
          System.exit(1);
     if (verbose) {
          int newMessages = folder.getNewMessageCount();
          System.out.println("Total messages = " + totalMessages);
          System.out.println("New messages = " + newMessages);
          System.out.println("-------------------------------");
     if (msgnum == -1) {
          // Attributes & Flags for all messages ..
          Message[] msgs = folder.getMessages();
          // Use a suitable FetchProfile
          FetchProfile fp = new FetchProfile();
          fp.add(FetchProfile.Item.ENVELOPE);
          fp.add(FetchProfile.Item.FLAGS);
          fp.add("X-Mailer");
          folder.fetch(msgs, fp);
          for (int i = 0; i < msgs.length; i++) {
          System.out.println("--------------------------");
          System.out.println("MESSAGE #" + (i + 1) + ":");
          dumpEnvelope(msgs);
          // dumpPart(msgs[i]);
     } else {
          System.out.println("Getting message number: " + msgnum);
          Message m = null;
          try {
          m = folder.getMessage(msgnum);
          dumpPart(m);
          } catch (IndexOutOfBoundsException iex) {
          System.out.println("Message number out of range");
     folder.close(false);
     store.close();
     } catch (Exception ex) {
     System.out.println("Oops, got exception! " + ex.getMessage());
     ex.printStackTrace();
     System.exit(1);
     System.exit(0);
public static void dumpPart(Part p) throws Exception {
     if (p instanceof Message)
     dumpEnvelope((Message)p);
     /** Dump input stream ..
     InputStream is = p.getInputStream();
     // If "is" is not already buffered, wrap a BufferedInputStream
     // around it.
     if (!(is instanceof BufferedInputStream))
     is = new BufferedInputStream(is);
     int c;
     while ((c = is.read()) != -1)
     System.out.write(c);
     String ct = p.getContentType();
     try {
     pr("CONTENT-TYPE: " + (new ContentType(ct)).toString());
     } catch (ParseException pex) {
     pr("BAD CONTENT-TYPE: " + ct);
     String filename = p.getFileName();
     if (filename != null)
     pr("FILENAME: " + filename);
     * Using isMimeType to determine the content type avoids
     * fetching the actual content data until we need it.
     if (p.isMimeType("text/plain")) {
     pr("This is plain text");
     pr("---------------------------");
     if (!showStructure && !saveAttachments)
          System.out.println((String)p.getContent());
     } else if (p.isMimeType("multipart/*")) {
     pr("This is a Multipart");
     pr("---------------------------");
     Multipart mp = (Multipart)p.getContent();
     level++;
     int count = mp.getCount();
     for (int i = 0; i < count; i++)
          dumpPart(mp.getBodyPart(i));
     level--;
     } else if (p.isMimeType("message/rfc822")) {
     pr("This is a Nested Message");
     pr("---------------------------");
     level++;
     dumpPart((Part)p.getContent());
     level--;
     } else {
     if (!showStructure && !saveAttachments) {
          * If we actually want to see the data, and it's not a
          * MIME type we know, fetch it and check its Java type.
          Object o = p.getContent();
          if (o instanceof String) {
          pr("This is a string");
          pr("---------------------------");
          System.out.println((String)o);
          } else if (o instanceof InputStream) {
          pr("This is just an input stream");
          pr("---------------------------");
          InputStream is = (InputStream)o;
          int c;
          while ((c = is.read()) != -1)
               System.out.write(c);
          } else {
          pr("This is an unknown type");
          pr("---------------------------");
          pr(o.toString());
     } else {
          // just a separator
          pr("---------------------------");
     * If we're saving attachments, write out anything that
     * looks like an attachment into an appropriately named
     * file. Don't overwrite existing files to prevent
     * mistakes.
     if (saveAttachments && level != 0 && !p.isMimeType("multipart/*")) {
     String disp = p.getDisposition();
     // many mailers don't include a Content-Disposition
     if (disp == null || disp.equalsIgnoreCase(Part.ATTACHMENT)) {
          if (filename == null)
          filename = "Attachment" + attnum++;
          pr("Saving attachment to file " + filename);
          try {
          File f = new File(filename);
          if (f.exists())
               // XXX - could try a series of names
               throw new IOException("file exists");
          ((MimeBodyPart)p).saveFile(f);
          } catch (IOException ex) {
          pr("Failed to save attachment: " + ex);
          pr("---------------------------");
public static void dumpEnvelope(Message m) throws Exception {
     pr("This is the message envelope");
     pr("---------------------------");
     Address[] a;
     // FROM
     if ((a = m.getFrom()) != null) {
     for (int j = 0; j < a.length; j++)
          pr("FROM: " + a[j].toString());
     // TO
     if ((a = m.getRecipients(Message.RecipientType.TO)) != null) {
     for (int j = 0; j < a.length; j++) {
          pr("TO: " + a[j].toString());
          InternetAddress ia = (InternetAddress)a[j];
          if (ia.isGroup()) {
          InternetAddress[] aa = ia.getGroup(false);
          for (int k = 0; k < aa.length; k++)
               pr(" GROUP: " + aa[k].toString());
     // SUBJECT
     pr("SUBJECT: " + m.getSubject());
     // DATE
     Date d = m.getSentDate();
     pr("SendDate: " +
     (d != null ? d.toString() : "UNKNOWN"));
     // FLAGS
     Flags flags = m.getFlags();
     StringBuffer sb = new StringBuffer();
     Flags.Flag[] sf = flags.getSystemFlags(); // get the system flags
     boolean first = true;
     for (int i = 0; i < sf.length; i++) {
     String s;
     Flags.Flag f = sf[i];
     if (f == Flags.Flag.ANSWERED)
          s = "\\Answered";
     else if (f == Flags.Flag.DELETED)
          s = "\\Deleted";
     else if (f == Flags.Flag.DRAFT)
          s = "\\Draft";
     else if (f == Flags.Flag.FLAGGED)
          s = "\\Flagged";
     else if (f == Flags.Flag.RECENT)
          s = "\\Recent";
     else if (f == Flags.Flag.SEEN)
          s = "\\Seen";
     else
          continue;     // skip it
     if (first)
          first = false;
     else
          sb.append(' ');
     sb.append(s);
     String[] uf = flags.getUserFlags(); // get the user flag strings
     for (int i = 0; i < uf.length; i++) {
     if (first)
          first = false;
     else
          sb.append(' ');
     sb.append(uf[i]);
     pr("FLAGS: " + sb.toString());
     // X-MAILER
     String[] hdrs = m.getHeader("X-Mailer");
     if (hdrs != null)
     pr("X-Mailer: " + hdrs[0]);
     else
     pr("X-Mailer NOT available");
static String indentStr = " ";
static int level = 0;
* Print a, possibly indented, string.
public static void pr(String s) {
     if (showStructure)
     System.out.print(indentStr.substring(0, level * 2));
     System.out.println(s);

Answer 1

Oh, I didn't specify any command line argument. I don't really get what arguments I should specify. Could please explain it to me. My main objective is to learn and be able to apply this to my personal project.
One more thing if you don't mind. I was very good at java (then I used Jdk 1.2) but I have lost touch due to not using Java for a very long time. I am also learning to Servlets at the moment but I just can't deploy it. In the past we used deploytool and I could get that to work but I just don't get how to deploy the servlet I wrote.
Thanks ever so much!