我试图从我的应用程序发送电子邮件。下面是一些代码。
String text = editText.getText().toString();
String to = "[email protected]";
String from = "[email protected]";
String host = "localhost";
Properties properties = System.getProperties();
properties.setProperty("mail.smtp.host", host);
Session session = Session.getDefaultInstance(properties);
try {
MimeMessage message = new MimeMessage(session);
message.setFrom(new InternetAddress(from));
message.addRecipient(Message.RecipientType.TO, new InternetAddress(to));
message.setSubject("Answer to your feedback");
message.setText(text);
Transport.send(message);
} catch (MessagingException mex){
mex.printStackTrace();
}
但是我得到了一个异常："Cause by: java.lang.reflect.InvocationTargetException at java.lang.reflect.Method.invoke(Native Method)
Caused by: java.lang.reflect.InvocationTargetException at java.lang.reflect.Method.invoke(Native Method) at androidx.appcompat.app.AppCompatViewInflater$DeclaredOnClickListener.onClick(AppCompatViewInflater. java:397) at android.View.View.performClick(View.java:7189) at android.View.View.performClickInternal(View.java:7163) at android.View.View.access$3500(View.java:821) at android.View.View$PerformClick. ActivityThread.main(ActivityThread.java:8147) at java.lang.reflect.Method.invoke(Native Method) at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:513) at com.android.internal. os.ZygoteInit.main(ZygoteInit.java:1101) 原因是：在android.os.StrictMode$AndroidBlockGuardPolicy.onNetwork(StrictMode.java:1565) 在java.net.Inet6AddressImpl. 在java.net.Inet6AddressImpl.lookupHostByName(Inet6AddressImpl.java:115) at java.net.Inet6AddressImpl.lookupAllHostAddr(Inet6AddressImpl.java:103) at java.net.InetAddress.getLocalHost(InetAddress.java:1488) at javax.mail.internet. InternetAddress.getLocalAddress(InternetAddress.java:517) at javax.mail.internet.UniqueValue.getUniqueMessageIDValue(UniqueValue.java:99) at javax.mail.internet.MimeMessage.updateMessageID(MimeMessage. javax.mail.internet.MimeMessage.updateHeaders(MimeMessage.java:2076) at javax.mail.internet.MimeMessage.saveChanges(MimeMessage.java:2042) at javax.mail.Transport.send(Transport.java:117)
没有找到任何有用的东西。我怎样才能解决这个问题？
正如堆栈告诉你的那样，你在主线程上做了网络连接，这是不可接受的，因为它可能会阻止UI的更新。查看AsyncTask并在那里执行你的代码。