在这里，我们希望发送带有附加txt文件的自动电子邮件，而无需用户 相互作用。所以，我们使用下面的代码。 它为GmailSender类抛出了NoClassDefinitionFound错误。 我们经历了这么多链接。我们没有找到任何解决方案。 谁能帮帮我吗。
**used jar files:-**
1.additionnal.jar
2.activation.jar
3.mail.jar
MainActivity.java
public class MainActivity extends Activity {
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
final Button send = (Button) this.findViewById(R.id.button1);
send.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
// TODO Auto-generated method stub
try {
GMailSender sender = new GMailSender("username@gmail.com", "password");// throwing error in this line
sender.sendMail("This is Subject",
"This is Body",
"user@gmail.com",
"user@yahoo.com");
} catch (Exception e) {
Log.e("SendMail", e.getMessage(), e);
}
}
});
}
}
//...........................................................................
GmailSender.java ：
class GMailSender extends javax.mail.Authenticator {
private String mailhost = "smtp.gmail.com";
private String user;
private String password;
private Session session;
static {
Security.addProvider(new JSSEProvider());
}
public GMailSender(String user, String password) {
this.user = user;
this.password = password;
Properties props = new Properties();
session = Session.getInstance(props, this);
props.setProperty("mail.transport.protocol", "smtp");
props.setProperty("mail.host", mailhost);
props.put("mail.smtp.ssl.enable","true");
props.put("mail.smtp.auth", "true");
props.put("mail.smtp.port", "465");
props.put("mail.smtp.socketFactory.port", "465");
props.put("mail.smtp.socketFactory.class","javax.net.ssl.SSLSocketFactory");
props.put("mail.smtp.socketFactory.fallback", "false");
props.setProperty("mail.smtp.quitwait", "false");
}
protected PasswordAuthentication getPasswordAuthentication() {
return new PasswordAuthentication(user, password);
}
public synchronized void sendMail(String subject, String body, String sender, String recipients) throws Exception {
try{
MimeMessage message = new MimeMessage(session);
DataHandler handler = new DataHandler(new ByteArrayDataSource(body.getBytes(), "text/plain"));
message.setSender(new InternetAddress(sender));
message.setSubject(subject);
message.setDataHandler(handler);
if (recipients.indexOf(',') > 0)
message.setRecipients(Message.RecipientType.TO, InternetAddress.parse(recipients));
else
message.setRecipient(Message.RecipientType.TO, new InternetAddress(recipients));
Transport.send(message);
}catch(Exception e){
}
}
public class ByteArrayDataSource implements DataSource, javax.activation.DataSource {
private byte[] data;
private String type;
public ByteArrayDataSource(byte[] data, String type) {
super();
this.data = data;
this.type = type;
}
public ByteArrayDataSource(byte[] data) {
super();
this.data = data;
}
public void setType(String type) {
this.type = type;
}
public String getContentType() {
if (type == null)
return "application/octet-stream";
else
return type;
}
public InputStream getInputStream() throws IOException {
return new ByteArrayInputStream(data);
}
public String getName() {
return "ByteArrayDataSource";
}
public OutputStream getOutputStream() throws IOException {
throw new IOException("Not Supported");
}
@Override
public PrintWriter getLogWriter() throws SQLException {
// TODO Auto-generated method stub
return null;
}
@Override
public int getLoginTimeout() throws SQLException {
// TODO Auto-generated method stub
return 0;
}
@Override
public void setLogWriter(PrintWriter out) throws SQLException {
// TODO Auto-generated method stub
}
@Override
public void setLoginTimeout(int seconds) throws SQLException {
// TODO Auto-generated method stub
}
@Override
public boolean isWrapperFor(Class<?> arg0) throws SQLException {
// TODO Auto-generated method stub
return false;
}
@Override
public <T> T unwrap(Class<T> arg0) throws SQLException {
// TODO Auto-generated method stub
return null;
}
@Override
public Connection getConnection() throws SQLException {
// TODO Auto-generated method stub
return null;
}
@Override
public Connection getConnection(String theUsername, String thePassword)
throws SQLException {
// TODO Auto-generated method stub
return null;
}
}
}
//................................................................................
JSSEProvider.java
public final class JSSEProvider extends Provider {
public JSSEProvider() {
super("HarmonyJSSE", 1.0, "Harmony JSSE Provider");
AccessController.doPrivileged(new java.security.PrivilegedAction<Void>() {
public Void run() {
put("SSLContext.TLS",
"org.apache.harmony.xnet.provider.jsse.SSLContextImpl");
put("Alg.Alias.SSLContext.TLSv1", "TLS");
put("KeyManagerFactory.X509",
"org.apache.harmony.xnet.provider.jsse.KeyManagerFactoryImpl");
put("TrustManagerFactory.X509",
"org.apache.harmony.xnet.provider.jsse.TrustManagerFactoryImpl");
return null;
}
});
}
}
AndroidManifest.xml权限：
添加了AndroidManifest.xml的权限：
1.<uses-permission android:name="android.permission.INTERNET" />
2.<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>
3.<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
4.<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"/>
堆栈追踪：
06-11 07:17:39.314: E/AndroidRuntime(2839): FATAL EXCEPTION: main
06-11 07:17:39.314: E/AndroidRuntime(2839): Process: com.example.mailex, PID: 2839
06-11 07:17:39.314: E/AndroidRuntime(2839): java.lang.NoClassDefFoundError: com.example.mailex.GMailSender
06-11 07:17:39.314: E/AndroidRuntime(2839): at com.example.mailex.MainActivity.emailsend(MainActivity.java:99)
06-11 07:17:39.314: E/AndroidRuntime(2839): at com.example.mailex.MainActivity.access$0(MainActivity.java:90)
06-11 07:17:39.314: E/AndroidRuntime(2839): at com.example.mailex.MainActivity$1.onClick(MainActivity.java:71)
06-11 07:17:39.314: E/AndroidRuntime(2839): at android.view.View.performClick(View.java:4438)
06-11 07:17:39.314: E/AndroidRuntime(2839): at android.view.View$PerformClick.run(View.java:18422)
06-11 07:17:39.314: E/AndroidRuntime(2839): at android.os.Handler.handleCallback(Handler.java:733)
06-11 07:17:39.314: E/AndroidRuntime(2839): at android.os.Handler.dispatchMessage(Handler.java:95)
06-11 07:17:39.314: E/AndroidRuntime(2839): at android.os.Looper.loop(Looper.java:136)
06-11 07:17:39.314: E/AndroidRuntime(2839): at android.app.ActivityThread.main(ActivityThread.java:5017)
06-11 07:17:39.314: E/AndroidRuntime(2839): at java.lang.reflect.Method.invokeNative(Native Method)
06-11 07:17:39.314: E/AndroidRuntime(2839): at java.lang.reflect.Method.invoke(Method.java:515)
06-11 07:17:39.314: E/AndroidRuntime(2839): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:779)
06-11 07:17:39.314: E/AndroidRuntime(2839): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:595)
06-11 07:17:39.314: E/AndroidRuntime(2839): at dalvik.system.NativeStart.main(Native Method)
感谢。