[Anroid] Send Mail From GMail SMTP (used JavaMail)

SP Hou
2 min readAug 6, 2020


Well, among all of send mail app, most used Intent.ACTION_SENDTO. But, Intent couldn’t send mail automatically. user need to click “ Send “ button form GMail APP. Actually, if we send mail automatically, APP is malicious to some degree. However, sometime we need function to send automatically ( secretly).

About the setting of gmail

First, we need to set up form Gmail setting page, turn on 低安全性應用程式存取權 and IMAP.

From the setting page, we know that hostname, port and SSL is true.

Here’s what this look like in code.
Don’t forget, class need to use AsyncTask.

2020/12/07 update
Well~ someday, I used those codes on Emulator again. But…I got the exception :

javax.mail.MessagingException: Could not connect to SMTP host: smtp.gmail.com, port: 465;
nested exception is:
javax.net.ssl.SSLHandshakeException: java.security.cert.CertPathValidatorException: Trust anchor for certification path not found.

The reason is … Firewall…..
After I turn off firewall at my computer, then I got the email that I send from APP.