JavaMail: Socket read timeout

问题

I'm using JavaMail and I want it to work through proxy for every threads (I have multithreading application). I'm using SMTPTransport.connect(Socket socket) for this.

Here is socket initialization:

socket = new Socket();
socket.setSoTimeout(10000);
socket.connect(new InetSocketAddress(smtpHost, smtpPort));

Here is SMTPTransport call:

SMTPTransport transport = null;
try
    {
     transport = (SMTPTransport) mail.getTransport("smtp");
     transport.connect(socket);
     System.out.println("ok");

And so on. But I this error happens:

DEBUG: JavaMail version 1.4.4 DEBUG: successfully loaded resource: /META-INF/javamail.default.providers DEBUG: Tables of loaded providers DEBUG: Providers Listed By Class Name: {com.sun.mail.smtp.SMTPSSLTransport=javax.mail.Provider[TRANSPORT,smtps,com.sun.mail.smtp.SMTPSSLTransport,Sun Microsystems, Inc], com.sun.mail.smtp.SMTPTransport=javax.mail.Provider[TRANSPORT,smtp,com.sun.mail.smtp.SMTPTransport,Sun Microsystems, Inc], com.sun.mail.imap.IMAPSSLStore=javax.mail.Provider[STORE,imaps,com.sun.mail.imap.IMAPSSLStore,Sun Microsystems, Inc], com.sun.mail.pop3.POP3SSLStore=javax.mail.Provider[STORE,pop3s,com.sun.mail.pop3.POP3SSLStore,Sun Microsystems, Inc], com.sun.mail.imap.IMAPStore=javax.mail.Provider[STORE,imap,com.sun.mail.imap.IMAPStore,Sun Microsystems, Inc], com.sun.mail.pop3.POP3Store=javax.mail.Provider[STORE,pop3,com.sun.mail.pop3.POP3Store,Sun Microsystems, Inc]} DEBUG: Providers Listed By Protocol: {imaps=javax.mail.Provider[STORE,imaps,com.sun.mail.imap.IMAPSSLStore,Sun Microsystems, Inc], imap=javax.mail.Provider[STORE,imap,com.sun.mail.imap.IMAPStore,Sun Microsystems, Inc], smtps=javax.mail.Provider[TRANSPORT,smtps,com.sun.mail.smtp.SMTPSSLTransport,Sun Microsystems, Inc], pop3=javax.mail.Provider[STORE,pop3,com.sun.mail.pop3.POP3Store,Sun Microsystems, Inc], pop3s=javax.mail.Provider[STORE,pop3s,com.sun.mail.pop3.POP3SSLStore,Sun Microsystems, Inc], smtp=javax.mail.Provider[TRANSPORT,smtp,com.sun.mail.smtp.SMTPTransport,Sun Microsystems, Inc]} DEBUG: successfully loaded resource: /META-INF/javamail.default.address.map DEBUG: getProvider() returning javax.mail.Provider[TRANSPORT,smtp,com.sun.mail.smtp.SMTPTransport,Sun Microsystems, Inc] DEBUG SMTP: useEhlo true, useAuth true DEBUG SMTP: useEhlo true, useAuth true DEBUG SMTP: starting protocol to host "smtp.googlemail.com", port 465 DEBUG SMTP: exception reading response: java.net.SocketTimeoutException: Read timed out Exception reading response javax.mail.MessagingException: Exception reading response; nested exception is: java.net.SocketTimeoutException: Read timed out at com.sun.mail.smtp.SMTPTransport.readServerResponse(SMTPTransport.java:2153) at com.sun.mail.smtp.SMTPTransport.openServer(SMTPTransport.java:1956) at com.sun.mail.smtp.SMTPTransport.protocolConnect(SMTPTransport.java:636) at javax.mail.Service.connect(Service.java:317) at javax.mail.Service.connect(Service.java:176) at javax.mail.Service.connect(Service.java:125) at com.sun.mail.smtp.SMTPTransport.connect(SMTPTransport.java:274) at lsmtpc.CheckAccount.run(CheckAccount.java:203) at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:471) at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:334) at java.util.concurrent.FutureTask.run(FutureTask.java:166) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1110) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:603) at java.lang.Thread.run(Thread.java:722) Caused by: java.net.SocketTimeoutException: Read timed out at java.net.SocketInputStream.socketRead0(Native Method) at java.net.SocketInputStream.read(SocketInputStream.java:150) at java.net.SocketInputStream.read(SocketInputStream.java:121) at com.sun.mail.util.TraceInputStream.read(TraceInputStream.java:110) at java.io.BufferedInputStream.fill(BufferedInputStream.java:235) at java.io.BufferedInputStream.read(BufferedInputStream.java:254) at com.sun.mail.util.LineInputStream.readLine(LineInputStream.java:89) at com.sun.mail.smtp.SMTPTransport.readServerResponse(SMTPTransport.java:2131) ... 13 more

So as I see JavaMail can't read from socket. So what am I doing wrong? If I try to use transport.connect() method without using Socket in constructor all works perfectly and smtpHost/smtpPort are accessible from the telnet and I have no any firewalls/antiviruses.

回答1:

From the documentation for com.sun.mail.smtp.SMTPTransport:

In general, applications should not need to use the classes in this package directly. Instead, they should use the APIs defined by javax.mail package (and subpackages). Applications should never construct instances of SMTPTransport directly. Instead, they should use the Session method getTransport to acquire an appropriate Transport object.

WARNING: The APIs unique to this package should be considered EXPERIMENTAL. They may be changed in the future in ways that are incompatible with applications using the current APIs.

JavaMail tutorial: http://java.sun.com/developer/onlineTraining/JavaMail/contents.html

Could be you are not passing authentication information. Could be you are connecting to a secured host using a plain socket. You might want to read the tutorial linked for the best way to use JavaMail.

来源：https://stackoverflow.com/questions/7557655/javamail-socket-read-timeout