FakeSMTP is a Free Fake SMTP Server written in Java. It is a stripped down version of Nilhcem/FakeSMTP. It will log all emails to one log file.
FakeSMTP uses SubEthaSMTP: an easy-to-use server-side SMTP library for Java.
FakeSMTP is free to use for commercial and non-commercial projects and the source code is provided.
It is licensed under the very free BSD or GPL license, whichever you prefer.
You need Java JVM 1.8 or newer installed on your machine.
If you are on a "Unix-like" machine (Mac, GNU/Linux, BSD...), you may have
to be "root" to start the port 25, otherwise, try another port >= 1024.
The fakeSMTP.jar is auto-executable. If your desktop environment supports it, you can directly double click on the .jar file. Otherwise, run the following command:
java -jar fakeSMTP-VERSION.jar
If you want to change the default port 25, you can use -p argument:
java -jar fakeSMTP-VERSION.jar -p 2525