为此我使用了以下代码：
package moin.sms;
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;
import android.os.Bundle;
import android.util.Log;
import android.widget.Button;
public class Mail extends javax.mail.Authenticator {
public String _user;
public 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 void 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 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;
}
public String[] getTo(){
return _to;
}
public void setTo(String[] _to){
this._to = _to;
}
public String getFrom(){
return _from;
}
public void setFrom(String _from){
this._from=_from;
}
public String getSubject(){
return _subject;
}
public void setSubject(String _subject){
this._subject=_subject;
}
}
调用此活动的活动如下：
package moin.sms;
import android.app.Activity;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
import android.widget.Toast;
public class GmailSendActivity extends Activity {
public void onCreate(Bundle icicle) {
super.onCreate(icicle);
setContentView(R.layout.main);
final TextView t1 = (TextView) findViewById(R.id.textView1);
Button addImage = (Button) findViewById(R.id.button1);
addImage.setOnClickListener(new View.OnClickListener() {
public void onClick(View view) {
Mail m = new Mail();
m._user = "**My Gmail ID**"; // username
m._pass = "**PASSWORD**"; // password
String[] toArr = {"cistoran@live.com", "ivan017@gmail.com"};
m.setTo(toArr);
m.setFrom("moin18@gmail.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(GmailSendActivity.this, "Email was sent successfully.", Toast.LENGTH_LONG).show();
} else {
Toast.makeText(GmailSendActivity.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);
}
t1.setText("to :"+m.getTo().toString()+"* from: "+m.getFrom()+"* Sub: "+m.getSubject()+"* Messg: "+m.getBody());
}
});
}
}
我已经添加了必要的罐子。即
（1）mail.jar
（2）activation.jar
（3）additional.jar
但是当我在Eclipse IDE中运行它时，LogCat上会显示以下错误消息：
02-10 11:20:06.682: E/MailApp(435): Could not send email
02-10 11:20:06.682: E/MailApp(435): java.lang.NullPointerException
02-10 11:20:06.682: E/MailApp(435): at moin.sms.Mail.addAttachment(Mail.java:117)
02-10 11:20:06.682: E/MailApp(435): at moin.sms.GmailSendActivity$1.onClick(GmailSendActivity.java:34)
02-10 11:20:06.682: E/MailApp(435): at android.view.View.performClick(View.java:2408)
02-10 11:20:06.682: E/MailApp(435): at android.view.View$PerformClick.run(View.java:8816)
02-10 11:20:06.682: E/MailApp(435): at android.os.Handler.handleCallback(Handler.java:587)
02-10 11:20:06.682: E/MailApp(435): at android.os.Handler.dispatchMessage(Handler.java:92)
02-10 11:20:06.682: E/MailApp(435): at android.os.Looper.loop(Looper.java:123)
02-10 11:20:06.682: E/MailApp(435): at android.app.ActivityThread.main(ActivityThread.java:4627)
02-10 11:20:06.682: E/MailApp(435): at java.lang.reflect.Method.invokeNative(Native Method)
02-10 11:20:06.682: E/MailApp(435): at java.lang.reflect.Method.invoke(Method.java:521)
02-10 11:20:06.682: E/MailApp(435): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:868)
02-10 11:20:06.682: E/MailApp(435): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:626)
02-10 11:20:06.682: E/MailApp(435): at dalvik.system.NativeStart.main(Native Method)
它甚至没有在手机上运行，我还在清单文件中添加了INTERNET权限。有人能告诉我们这里的问题吗？
答案 0 :(得分：0)
我从你的LogCat问题中了解到的是代码片段： -
m.addAttachment("/sdcard/filelocation");
你究竟想用邮件附上什么？
答案 1 :(得分：0)
您应该尝试m.addAttachment("/mnt/sdcard/filelocation");
甚至更好：
Environment.getExternalStorageDirectory().getAbsolutePath() + File.separator + "myaudio.3gpp"
另外，检查您是否在清单中添加了以下权限：
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />