I am making use of Java Mail API to develop an app to send mail. I can successfully send the mail if I use the mail server hosting by yahoo or gmail. However, when I try to use my own mail server, I am fail to send the mail, what are the possible reasons causing the failure? When I execute my app in my device, it displays "Email was not sent", so no exception occurs. May I ask how can I change my program so I can successfully connect my app to my smtp server, or how can I get more information to display therefore I can understand why the connection has failed.
Here is my program: Sender.java
public class Sender extends Activity {
Button Send;
TextView text;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_sender);
Send = (Button) findViewById(R.id.mail);
text = (TextView) findViewById(R.id.textView1);
StrictMode.ThreadPolicy policy = new StrictMode.ThreadPolicy.Builder()
.permitAll().build();
StrictMode.setThreadPolicy(policy);
Send.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
new SendMail().execute();
}
});
}
private class SendMail extends AsyncTask<String, Void, Integer>
{
ProgressDialog pd = null;
String error = null;
Integer result;
@Override
protected void onPreExecute() {
// TODO Auto-generated method stub
super.onPreExecute();
pd = new ProgressDialog(Sender.this);
pd.setTitle("Sending Mail");
pd.setMessage("Please wait...");
pd.setCancelable(false);
pd.show();
}
@Override
protected Integer doInBackground(String... params) {
// TODO Auto-generated method stub
MailSender sender = new MailSender("me@mysmtp.com", "password");
sender.setTo(new String[]{"you@mysmtp.com", "me@gmail.com"});
sender.setFrom("me@mysmtp.com");
sender.setSubject("Test mail");
sender.setBody("This is the mail body");
try {
if(sender.send()) {
System.out.println("Message sent");
return 1;
} else {
return 2;
}
} catch (Exception e) {
error = e.getMessage();
Log.e("SendMail", e.getMessage(), e);
}
return 3;
}
protected void onPostExecute(Integer result) {
pd.dismiss();
if(error!=null) {
text.setText(error);
}
if(result==1) {
Toast.makeText(Sender.this,
"Email was sent successfully.", Toast.LENGTH_LONG)
.show();
} else if(result==2) {
Toast.makeText(Sender.this,
"Email was not sent.", Toast.LENGTH_LONG).show();
} else if(result==3) {
Toast.makeText(Sender.this,
"There was a problem sending the email.",
Toast.LENGTH_LONG).show();
}
}
}
}
MailSender.java
public class MailSender extends Authenticator {
private String user;
private String password;
private String [] to;
private String from;
private String port;
private String sport;
private String host;
private String subject;
private String body;
private boolean auth;
private boolean debuggable;
private Multipart multi;
public MailSender(){
host = "web.mysmtp.com";
port = "25";
sport = "25";
user = "";
password = "";
from = "";
subject = "";
body = "";
debuggable = false;
auth = true;
multi = new MimeMultipart();
// There is something wrong with MailCap, javamail can not find a handler for the multipart/mixed part, so this bit needs to be added.
MailcapCommandMap mc = (MailcapCommandMap) CommandMap.getDefaultCommandMap();
mc.addMailcap("text/html;; x-java-content-handler=com.sun.mail.handlers.text_html");
mc.addMailcap("text/plain;; x-java-content-handler=com.sun.mail.handlers.text_plain");
mc.addMailcap("multipart/*;; x-java-content-handler=com.sun.mail.handlers.multipart_mixed");
mc.addMailcap("message/rfc822;; x-java-content-handler=com.sun.mail.handlers.message_rfc822");
CommandMap.setDefaultCommandMap(mc);
}
public MailSender(String user, String password){
this();
this.user = user;
this.password = password;
}
public boolean send() throws Exception {
Properties props = setProperties();
try{
Session session = Session.getInstance(props, this);
session.setDebug(true);
MimeMessage msg = new MimeMessage(session);
msg.setFrom(new InternetAddress(from));
InternetAddress[] addressTo = new InternetAddress[to.length];
for(int i=0; i<to.length; i++){
addressTo[i] = new InternetAddress(to[i]);
}
msg.setRecipients(MimeMessage.RecipientType.TO, addressTo);
msg.setSubject(subject);
msg.setSentDate(new Date());
BodyPart messageBodyPart = new MimeBodyPart();
messageBodyPart.setText(body);
multi.addBodyPart(messageBodyPart);
msg.setContent(multi);
Transport transport = session.getTransport("smtps");
transport.connect(host, 25, user, password);
transport.sendMessage(msg, msg.getAllRecipients());
transport.close();
return true;
} catch (Exception e) {
e.printStackTrace();
return false;
}
}
public void addAttachment(String filename) throws Exception {
BodyPart messageBodyPart = new MimeBodyPart();
DataSource source = new FileDataSource(filename);
messageBodyPart.setDataHandler(new DataHandler(source));
messageBodyPart.setFileName(filename);
multi.addBodyPart(messageBodyPart);
}
@Override
public PasswordAuthentication getPasswordAuthentication() {
return new PasswordAuthentication(user, password);
}
private Properties setProperties() {
Properties props = new Properties();
props.put("mail.smtp.host", host);
if(debuggable) {
props.put("mail.debug", "true");
}
if(auth) {
props.put("mail.smtp.auth", "true");
}
props.put("mail.smtp.port", port);
props.put("mail.smtp.socketFactory.port", sport);
props.put("mail.smtp.socketFactory.class", "javax.net.ssl.SSLSocketFactory");
props.put("mail.smtp.socketFactory.fallback", "false");
return props;
}
public void setTo(String[] toAddress) {
this.to = toAddress;
}
public void setFrom(String fromAddress) {
this.from = fromAddress;
}
public void setSubject(String subject) {
this.subject = subject;
}
public void setBody(String body) {
this.body = body;
}
}
Error messages in error log:
08-15 11:21:37.284: W/System.err(2553): javax.net.ssl.SSLHandshakeException: javax.net.ssl.SSLProtocolException: SSL handshake aborted: ssl=0x5c075548: Failure in SSL library, usually a protocol error
08-15 11:21:37.291: W/System.err(2553): Caused by: javax.net.ssl.SSLHandshakeException: javax.net.ssl.SSLProtocolException: SSL handshake aborted: ssl=0x5c075548: Failure in SSL library, usually a protocol error
08-15 11:21:37.299: W/System.err(2553): Caused by: javax.net.ssl.SSLProtocolException: SSL handshake aborted: ssl=0x5c075548: Failure in SSL library, usually a protocol error
You're connecting to port 25 and using SSL. Port 25 is the non-SSL (plain text) port. Assuming your server is set up for SSL, use the connect method that doesn't require you to specify a port number and let JavaMail use the default port.
The SSL configuration of your SMTP server would be the first thing i'd check. If your class works with the external services then it's a security configuration of your server.
You are probably getting that error because you did not create a signed cert on the server side. If you did set up the SSL verification, you either did not do it correctly or you are connecting to a server whose cert hasn't been added to the truststore.
This post ( How Can I Access an SSL Connection Through Android? ) has an answer with a code sample as to how you can initialize your keystore and truststore.
Java Mail API causes a lot of problems, here are my working examples for various pop3/smtp connections, which I recently tested with few different mail servers.
来源：https://stackoverflow.com/questions/11963587/sslexception-in-using-javamail-api