java 如何更正无效协议：使用 javax.mail 发送空邮件
声明：本页面是StackOverFlow热门问题的中英对照翻译，遵循CC BY-SA 4.0协议，如果您需要使用它，必须同样遵循CC BY-SA许可，注明原文地址和作者信息，同时你必须将它归于原作者（不是我）：StackOverFlow
原文地址: http://stackoverflow.com/questions/11265755/
Warning: these are provided under cc-by-sa 4.0 license. You are free to use/share it, But you must attribute it to the original authors (not me):
StackOverFlow
How to correct Invalid Protocol: null sending mail using javax.mail
提问by HymanTurky
i'm trying to send mail in this way:
我正在尝试以这种方式发送邮件：
Properties props = new Properties();
props.setProperty("mail.transport.protocol", "smtp");
props.setProperty("mail.host", "out.alice.it");
props.setProperty("mail.user", "[email protected]");
props.setProperty("mail.password", "*****");
Session mailSession = Session.getDefaultInstance(props, null);
Transport transport = mailSession.getTransport();
MimeMessage message = new MimeMessage(mailSession);
message.setFrom(new InternetAddress("Host", "Name"));
On the row Transport transport...i retrieve this error:
在这一行Transport transport...我检索到这个错误：
javax.mail.NoSuchProviderException: Invalid protocol: null
at javax.mail.Session.getProvider(Session.java:440)
at javax.mail.Session.getTransport(Session.java:659)
at javax.mail.Session.getTransport(Session.java:640)
at javax.mail.Session.getTransport(Session.java:626)
at Mail.sendMail(Mail.java:151)
How can i resolve? Can someone help me? Thanks!! :)
我该如何解决？有人能帮我吗？谢谢！！:)
EDIT:
编辑：
If i create a main and launch that method to send mail, it works good! My problem borns after i read mail into mail folder:
如果我创建一个 main 并启动该方法来发送邮件，它运行良好！我的问题是在我将邮件读入邮件文件夹后产生的：
Properties properties = System.getProperties();
properties.setProperty("mail.store.protocol", "imap");
Session session = Session.getDefaultInstance(properties, null);
Store store = session.getStore("pop3");
store.connect("pop3.domain.it", "[email protected]", "****");
Folder inbox = store.getFolder("inbox");
FlagTerm ft = new FlagTerm(new Flags(Flags.Flag.SEEN), false);
inbox.open(Folder.READ_ONLY);
Message messages[] = inbox.search(ft);
for(Message message:messages) {
if(message.getFrom()[0].toString().equals("aMail")){
sendMail(message.getFrom()[0].toString());//Error!
}
}
I Thought the exception borns cause i've opened store to get inbox mail so i edit in this way:
我认为异常的原因是因为我打开了商店来接收收件箱邮件，所以我以这种方式进行编辑：
ArrayList<String> reply = new ArrayList<String();
for(Message message:messages) {
if(message.getFrom()[0].toString().equals("aMail")){
reply.add(message.getFrom()[0].toString());
}
}
store.close();
for(String mail : reply){
sendMail(mail); // ERROR AGAIN!
}
very strange....
很奇怪....
SOLVED IN THIS WAY:
以这种方式解决：
i modified this row
我修改了这一行
Session mailSession = Session.getDefaultInstance(props, null);
to
到
Session mailSession = Session.getInstance(props);
采纳答案by Pavel K.
you might try another way:
你可以尝试另一种方式：
Properties props = new Properties();
props.setProperty("mail.transport.protocol", "smtp");
props.setProperty("mail.smtp.host", "out.alice.it");
props.setProperty("mail.smtp.auth", "true");
final PasswordAuthentication auth = new PasswordAuthentication(smtpUser, stmpPassword);
Session mailSession = Session.getDefaultInstance(props, new Authenticator() {
@Override
protected PasswordAuthentication getPasswordAuthentication() { return auth; }
});
MimeMessage message = ....;
// compose the message
Transport.send(message);
回答by Dr.Octoboz
I was getting this same error, and my problem was I forgot to include:
我遇到了同样的错误，我的问题是我忘了包括：
props.put("mail.transport.protocol", "smtp");
