Code improvements

[JarFiles]

• Custom exception instead of just printing the error
• Don't use raw types for parametized classess
• Use Apache's Lang Validator (Because it has a better ide implementation)
• Code Formatting / Naming is sometimes a bit inconsistent (Throwable e / Throwable ex)
• Always use the absolute filepath in error messages. Makes debugging a lot simpler

[KotlinFactory]

Hey Just,

Thank you for providing these enhancements. We will consider adding it.

Regards,

• Leonhard