package com.example.mailtest;import java.util.Date; import java.util.Properties; import javax.activation.CommandMap; import javax.activation.DataHandler; import javax.activation.DataSource; import javax.activation.FileDataSource; import javax.activation.MailcapCommandMap; import javax.mail.BodyPart; import javax.mail.Multipart; import javax.mail.PasswordAuthentication; import javax.mail.Session; import javax.mail.Transport; import javax.mail.internet.InternetAddress; import javax.mail.internet.MimeBodyPart; import javax.mail.internet.MimeMessage; import javax.mail.internet.MimeMultipart;   public class Mail extends javax.mail.Authenticator {  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 = ""; // username  _pass = ""; // password  _from = ""; // email sent from  _subject = ""; // email subject  _body = ""; // 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 Mail(String user, String pass) {  this();   _user = user;  _pass = pass;  }  public void setTo(String[] toArr) { this._to = toArr; }  public void setFrom(String string) { this._from = string; }  public void setSubject(String string) { this._subject = string; } public boolean send() throws Exception {  Properties props = _setProperties();   if(!_user.equals("") && !_pass.equals("") && _to.length > 0 && !_from.equals("") && !_subject.equals("") && !_body.equals("")) {  Session session = Session.getInstance(props, this);   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());   // 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);  }   @Override  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;  }   // more of the getters and setters ….. } 

package com.example.mailtest;  import java.util.Properties; import javax.mail.Address;import javax.mail.Message;import javax.mail.Session;import javax.mail.Transport;import javax.mail.internet.InternetAddress;import javax.mail.internet.MimeMessage;    import android.os.AsyncTask;import android.os.Bundle;import android.os.Handler;import android.app.Activity;import android.app.ProgressDialog;import android.util.Log;import android.view.Menu;import android.view.View;import android.widget.Button;import android.widget.Toast; public class MailActivity extends Activity {  private Button sendBtn; private String username; private String password; private Handler sendHandler; private ProgressDialog progressDialog; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_mail); sendBtn=(Button)findViewById(R.id.btnSend); sendHandler = new Handler(); sendBtn.setOnClickListener(new View.OnClickListener() {  public void onClick(View v) {  SendTask sTask = new SendTask();  sTask.execute(); }  });   }   @Override public boolean onCreateOptionsMenu(Menu menu) { // Inflate the menu; this adds items to the action bar if it is present. getMenuInflater().inflate(R.menu.activity_mail, menu); return true; }    class SendTask extends AsyncTask<Integer, Integer, String>{  //后面尖括號內分別是參數（例子里是線程休息時間），進度(publishProgress用到)，返回值 類型   @Override  protected void onPreExecute() {  //第一個執行方法  Toast.makeText(getApplicationContext(), "Begin Send!", Toast.LENGTH_SHORT).show();  super.onPreExecute();  }   @Override  protected String doInBackground(Integer... params) {  //第二個執行方法,onPreExecute()執行完后執行  // TODO Auto-generated method stub  Mail m = new Mail("[email protected]", "*****");   String[] toArr = {"[email protected]","[email protected]"};  m.setTo(toArr);  m.setFrom("[email protected]");  m.setSubject("JavamailTest");  m.setBody("Email body.");   try { //If you want add attachment use function addAttachment. //m.addAttachment("/sdcard/filelocation");   if(m.send()) {   System.out.println("Email was sent successfully.");  } else {   System.out.println("Email was not sent."); }  } 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);  }  return "";  }   @Override  protected void onProgressUpdate(Integer... progress) {  //這個函數在doInBackground調用publishProgress時觸發，雖然調用時只有一個參數  //但是這里取到的是一個數組,所以要用progesss[0]來取值  //第n個參數就用progress[n]來取值   super.onProgressUpdate(progress);  }   @Override  protected void onPostExecute(String r) {  //doInBackground返回時觸發，換句話說，就是doInBackground執行完后觸發  //這里的result就是上面doInBackground執行后的返回值，所以這里是"執行完畢"  //setTitle(result);  super.onPostExecute(r);  }   }  }

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent" android:layout_height="match_parent" tools:context=".MailActivity" >  <TextView  android:layout_width="wrap_content"  android:layout_height="wrap_content"  android:layout_centerHorizontal="true"  android:layout_centerVertical="true"  android:text="@string/hello_world" />  <Button  android:id="@+id/btnSend"  android:layout_width="wrap_content"  android:layout_height="wrap_content"  android:layout_alignParentLeft="true"  android:layout_alignParentTop="true"  android:layout_marginTop="19dp"  android:text="Send" /> </RelativeLayout>