# Guidelines

This collection gives you an overview about the guidelines we are follow to improve our teamwork.

# 1. Contribution Guidelines

# 1.1 Pull Requests

1. Make sure you respect all language specific code guidelines.
2. Make sure you that you not modified any IDE settings files as long as the changes are not related to you pull request.
3. Please do not reformat code sections if not required. Always try to follow the project related code formatting rules.
4. Do not include useless modifications such as changing white spaces..
5. No one is happy to criticize your code changes. Therefore, please perform your own code review before submitting any pull requests since this can save project maintainer a huge amount of time during the code revise.
   • To do so, change into the branch you wanna submit and check all changes against the project master branch. Therefore, use git to track all changes: git diff --word-diff master

# 2. Code Guidelines

# 2.3 Java

1. Please never return null in any methods bodies since this can easily lead to NullpointerExceptions.
   • Use void instead if there is nothing to return or throw an CouldNotPerformException in error cases.
2. Please do not use boolean as return values to indicate success or error of a method execution.
   • Thats what Exception are good for. Therefore, throw an CouldNotPerformException in error cases.
3. Do not just print exceptions via System.out / System.err or by passing the exception to any logger print.
   • Please use the ExceptionPrinter.printHistory(...) for printing any exceptions.
4. Declare global and local variables always final if useful.
5. Always use org.slf4j as logging framework since its an logger abstraction layer which enables one to exchange the logger backend later without any code modifications.
   • Therefore, try to avoid logging via System.in / System.err

# 3. Project Guidelines

# 3.1 License

• Include the license file on top-level in any project repository.

# 3.2 Installer

• Provide an install.sh script in any repository which enables an easy installation of the application. Furthermore, try to minimize external dependencies such as using multiple build tools and warn if those are not available.