请问：我用JavaMail编的程序问什么不能收取某些imap邮件

koyee 2001-07-20 06:10:24

我用的是demo里的程序msgshow.java的一部分，有的信箱可以，有的不能读取正文，21cn.com就是。以下是源代码
/*
* @(#)msgshow.java 1.24 00/10/14
*
* Copyright 1997-2000 Sun Microsystems, Inc. All Rights Reserved.
*
* Sun grants you ("Licensee") a non-exclusive, royalty free, license to use,
* modify and redistribute this software in source and binary code form,
* provided that i) this copyright notice and license appear on all copies of
* the software; and ii) Licensee does not utilize the software in a manner
* which is disparaging to Sun.
*
* This software is provided "AS IS," without a warranty of any kind. ALL
* EXPRESS OR IMPLIED CONDITIONS, REPRESENTATIONS AND WARRANTIES, INCLUDING ANY
* IMPLIED WARRANTY OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE OR
* NON-INFRINGEMENT, ARE HEREBY EXCLUDED. SUN AND ITS LICENSORS SHALL NOT BE
* LIABLE FOR ANY DAMAGES SUFFERED BY LICENSEE AS A RESULT OF USING, MODIFYING
* OR DISTRIBUTING THE SOFTWARE OR ITS DERIVATIVES. IN NO EVENT WILL SUN OR ITS
* LICENSORS BE LIABLE FOR ANY LOST REVENUE, PROFIT OR DATA, OR FOR DIRECT,
* INDIRECT, SPECIAL, CONSEQUENTIAL, INCIDENTAL OR PUNITIVE DAMAGES, HOWEVER
* CAUSED AND REGARDLESS OF THE THEORY OF LIABILITY, ARISING OUT OF THE USE OF
* OR INABILITY TO USE SOFTWARE, EVEN IF SUN HAS BEEN ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGES.
*
* This software is not designed or intended for use in on-line control of
* aircraft, air traffic, aircraft navigation or aircraft communications; or in
* the design, construction, operation or maintenance of any nuclear
* facility. Licensee represents and warrants that it will not use or
* redistribute the Software for such purposes.
*/

import java.util.*;
import java.io.*;
import javax.mail.*;
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 = "INBOX";
static String url = null;
static int port = -1;
static boolean verbose = false;
static boolean debug = false;
static boolean showStructure = false;
static boolean showMessage = false;

public static void main(String argv[]) {
int msgnum = -1;
int optind;

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("-m")) {
showMessage = 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]");
System.out.println(
"or msgshow -m [-v] [-D] [-s] < msg");
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.getDefaultInstance(props, null);
session.setDebug(debug);

if (showMessage) {
MimeMessage msg = new MimeMessage(session, System.in);
dumpPart(msg);
System.exit(0);
}

// Get a Store object
Store store = null;
if (url != null) {
URLName urln = new URLName(url);
store = session.getStore(urln);
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);
}

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[i]);
// 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);

**/

pr("CONTENT-TYPE: " + p.getContentType());
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)
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) {
/*
* 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 {
pr("This is an unknown type");
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());
}

// 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);
}
}

...全文