我正在使用JavaMail APi发送电子邮件而没有来自我的Android应用程序的意图。我正在关注这个问题： Sending Email in Android using JavaMail API without using the default/built-in app
和
http://www.jondev.net/articles/Sending_Emails_without_User_Intervention_(no_Intents)_in_Android
这是我的代码。在按钮上单击以下是代码：
public void onClick(View v){
Runnable runnable = new Runnable(){
@Override
public void run() {
Mail m = new Mail("MY Gmail Address", "My password");
String[] toArr = {"sender@gmail.com"};
m.setTo(toArr);
m.setFrom("wooo@wooo.com");
m.setSubject("This is an email sent using my Mail JavaMail wrapper from an Android device.");
m.setBody("Email body.");
try {
m.addAttachment("/sdcard/filelocation");
if(m.send()) {
Toast.makeText(MyActivity.this, "Email was sent successfully.", Toast.LENGTH_LONG).show();
} else {
Toast.makeText(MyActivity.this, "Email was not sent.", Toast.LENGTH_LONG).show();
}
} catch(Exception e) {
//Toast.makeText(MailApp.this, "There was a problem sending the email.", Toast.LENGTH_LONG).show();
Log.e("MailApp", "Could not send email", e);
}
}
};
new Thread(runnable).start();
}
课程如下：
public class Mail { private String _user; private String _pass;
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 _multipart;
public Mail() {
_host = "smtp.gmail.com"; // default smtp server
_port = "465"; // default smtp port
_sport = "465"; // default socketfactory port
_user = "My mail id"; // username
_pass = "My Password"; // password
_from = ""; // email sent from
_subject = "Hi"; // email subject
_body = "how are you"; // email body
_debuggable = false; // debug mode on or off - default off
_auth = true; // smtp authentication - default on
_multipart = 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/xml;; x-java-content-handler=com.sun.mail.handlers.text_xml");
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 void setFrom(String string) {
// TODO Auto-generated method stub
_from="from email address";
}
public void setSubject(String string) {
// TODO Auto-generated method stub
_subject="Hi";
}
public void setTo(String[] toArr) {
// TODO Auto-generated method stub
_to = "to email address";
}
public Mail(String user, String pass) {
this();
_user = user;
_pass = pass;
}
public boolean send() throws Exception {
Properties props = _setProperties();
if(!_user.equals("") && !_pass.equals("") && !_from.equals("") && !_subject.equals("") && !_body.equals("")) {
Session session = Session.getInstance(props);
MimeMessage msg = new MimeMessage(session);
msg.setFrom(new InternetAddress(_from));
//InternetAddress[] addressTo = new InternetAddress[_to.toString()];
/*for (int i = 0; i < _to.length; i++) {
addressTo[i] = new InternetAddress(_to[i]);
}*/
msg.setRecipient(MimeMessage.RecipientType.TO, new InternetAddress(_to));
msg.setSubject(_subject);
// setup message body
BodyPart messageBodyPart = new MimeBodyPart();
messageBodyPart.setText(_body);
_multipart.addBodyPart(messageBodyPart);
// Put parts in message
msg.setContent(_multipart);
// send email
Transport.send(msg);
return true;
} else {
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);
_multipart.addBodyPart(messageBodyPart);
}
public PasswordAuthentication getPasswordAuthentication() {
return new PasswordAuthentication(_user, _pass);
}
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;
}
// the getters and setters
public String getBody() {
return _body;
}
public void setBody(String _body) {
this._body = _body;
}
当我点击Android设备上的按钮时，它会给我以下错误：
06-12 13:26:42.523: E/MailApp(8579): Could not send email
06-12 13:26:42.523: E/MailApp(8579): java.lang.NullPointerException
06-12 13:26:42.523: E/MailApp(8579): at com.MyApp.MyActivity$Mail.send(MyActivity.java:280)
06-12 13:26:42.523: E/MailApp(8579): at com.MyApp.MActivity$1.run(MActivity.java:146)
06-12 13:26:42.523: E/MailApp(8579): at java.lang.Thread.run(Thread.java:1019)
我错过了什么吗？
答案 0 :(得分：1)
你班上哪一行是第280行？它应该在你的Mail.send（）函数中。这是空指针所在的位置。知道那是什么会很有帮助。
看起来_to从未初始化......
哈哈，不用担心，我花了几个月的时间才能从javamail中获得一个有效的电子邮件客户端。创建会话时，应该向其传递一个身份验证对象..
SMTPAuthenticator auth = new SMTPAuthenticator();
session = Session.getDefaultInstance(props,auth);
private class SMTPAuthenticator extends javax.mail.Authenticator {
public PasswordAuthentication getPasswordAuthentication() {
String username = "your_username";
String password = "your_password";
return new PasswordAuthentication(username, password);
}
}