In the following example, we are going to send a plain text email to a recipient. As shown in the previous section, we will need to have an SMTP server available to enable us to send emails to the desired recipients. In this example and the next ones, we will use Gmail as our SMTP relay server.
Note
Note: I highly recommend registering a new email address for testing purposes, and not using your current main one. This is because you may somehow forget your own credentials are inside the code, and they might be viewed by someone later. Moreover, if you have not enabled two-way authentication, it's better to quickly enable this mode now!
Create a test method space to run your example, either in a servlet or a JAX-RS service, then write the following code inside it:
// recipient mail: replace by your main email: String to = "****@gmail.com"; // sender mail and credentials: replace by your testing email: String from = "****@gmail.com"; final String username = "****@gmail.com...