System properties are only read if configuration file exists in class path

[mriegler]

Actual behaviour

Configuration via system properties is ignored as long as there is no "simplejavamail.properties" file in the class path.

Expected behaviour

Configuration via system properties is possible, even without a properties file.

Why it happens

This is because the ConfigLoader loadProperties that gets called in the static init block does NOT call readProperties. readProperties is where the system properties are used if set.

The loadProperties variant for InputStream does call readProperties, but is itself only called if the loadProperties for String finds a file on the class path.

Ergo to enable system properties you need to add a file to the class path.

How to reproduce

• Use a basic builder, with no explicit optional settings, letting defaults happen
• set a system property (for example simplejavamail.defaults.verifyserveridentity) to any valid, non-default value (e.g. false)
• Check the setting in the Config of the Mailer the Builder built. In this example, OperationConfig isVerifyingIdentity should be false, but is true
• add an empty "simplejavamail.properties" file to the classpath
• Check the setting again. This time, it will have the correct value