What does IOException mean on a javamail IMAPS connection? - imap

Question

I'm trying to connect to an exchange server with IMAPS on port 443 (it's been configured this way on the other end) using the following code:
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props.setProperty("javax.net.ssl.trustStore", "C:/Program Files/Java/jdk1.6.0_30/jre/lib/security/cacerts");
props.setProperty("javax.net.ssl.trustStorePassword", "changeit");
props.setProperty("javax.net.ssl.trustStoreType", "jks");
props.setProperty("javax.net.debug", "ssl");
System.setProperties(props);
props = System.getProperties();
final Session session = Session.getInstance(props, null);
session.setDebug(debug);
com.sun.mail.imap.IMAPFolder inbox = null;
Store store = null;
store = session.getStore("imaps");
store.connect(host, 443, username, password);
inbox = (com.sun.mail.imap.IMAPFolder) store.getFolder("INBOX");
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Judging from the fact that I get no certificate errors, they are correctly loaded from the store location. However, I get the following trace once the code reaches the connect statement:"
[29/01/13 18:23:02:811 CST] 0000007d SystemOut O DEBUG: getProvider() returning javax.mail.Provider[STORE,imaps,com.sun.mail.imap.IMAPSSLStore,Sun Microsystems, Inc]
[29/01/13 18:23:02:812 CST] 0000007d SystemOut O DEBUG: mail.imap.fetchsize: 16384
[29/01/13 18:18:42:814 CST] 0000007d SystemErr R javax.mail.MessagingException;
nested exception is:
java.io.IOException
[29/01/13 18:18:42:814 CST] 0000007d SystemErr R at com.sun.mail.imap.IMAPStore.protocolConnect(IMAPStore.java:479)
[29/01/13 18:18:42:814 CST] 0000007d SystemErr R at javax.mail.Service.connect(Service.java:275)
[29/01/13 18:18:42:814 CST] 0000007d SystemErr R at com.scots.utils.MailPoller$1.run(MailPoller.java:74)
[29/01/13 18:18:42:815 CST] 0000007d SystemErr R at java.lang.Thread.run(Thread.java:738)
[29/01/13 18:18:42:815 CST] 0000007d SystemErr R Caused by: java.io.IOException
[29/01/13 18:18:42:815 CST] 0000007d SystemErr R at com.sun.mail.iap.ResponseInputStream.read0(ResponseInputStream.java:99)
[29/01/13 18:18:42:815 CST] 0000007d SystemErr R at com.sun.mail.iap.ResponseInputStream.readResponse(ResponseInputStream.java:67)
[29/01/13 18:18:42:815 CST] 0000007d SystemErr R at com.sun.mail.iap.Response.<init>(Response.java:83)
[29/01/13 18:18:42:815 CST] 0000007d SystemErr R at com.sun.mail.imap.protocol.IMAPResponse.<init>(IMAPResponse.java:48)
[29/01/13 18:18:42:815 CST] 0000007d SystemErr R at com.sun.mail.imap.protocol.IMAPResponse.readResponse(IMAPResponse.java:122)
[29/01/13 18:18:42:815 CST] 0000007d SystemErr R at com.sun.mail.imap.protocol.IMAPProtocol.readResponse(IMAPProtocol.java:230)
[29/01/13 18:18:42:815 CST] 0000007d SystemErr R at com.sun.mail.iap.Protocol.<init>(Protocol.java:91)
[29/01/13 18:18:42:815 CST] 0000007d SystemErr R at com.sun.mail.imap.protocol.IMAPProtocol.<init>(IMAPProtocol.java:87)
[29/01/13 18:18:42:815 CST] 0000007d SystemErr R at com.sun.mail.imap.IMAPStore.protocolConnect(IMAPStore.java:446)
[29/01/13 18:18:42:816 CST] 0000007d SystemErr R ... 3 more
And nothing else! I've searched everywhere for the possible meanings or causes for an IOException thrown during the connect execution, but I've got nothing so far.
Given that the stacktrace doesn't go any further and the only line of my own code referenced in it is the connect statement itself (com.scots.utils.MailPoller$1.run(MailPoller.java:74), I really don't have much to go on.
The only thing that comes to mind that could be causing throuble is that I've put the mail polling mechanics inside another thread (a run method). Could that be causing trouble?
Any ideas you could provide will be greatly appreciated!
Thanks in advance.

Answer 1

There's not much information in the exceptions, but I think the underlying cause is most likely that you really aren't handling the SSL connection properly. The JavaMail SSLNOTES.txt file has some debugging tips and pointers.