Coding Style

Like all development teams, the Dataverse developers at IQSS have their habits and styles when it comes to writing code. Let’s attempt to get on the same page. :)

Java

Formatting Code

Rules can be seen here: https://wiki.yadda.icm.edu.pl/yadda/Public:Coding_conventions

Format Code You Changed with Netbeans

IQSS has standardized on Netbeans. It is much appreciated when you format your code (but only the code you touched!) using the out-of-the-box Netbeans configuration. If you have created an entirely new Java class, you can just click Source -> Format. If you are adjusting code in an existing class, highlight the code you changed and then click Source -> Format. Keeping the “diff” in your pull requests small makes them easier to code review.

Checking Your Formatting With Checkstyle

The easiest way to adopt Dataverse coding style is to use Netbeans as your IDE, avoid change the default Netbeans formatting settings, and only reformat code you’ve changed, as described in Format Code You Changed with Netbeans.

If you do not use Netbeans, you are encouraged to check the formatting of your code using Checkstyle.

To check the entire project:

mvn checkstyle:checkstyle

To check a single file:

mvn checkstyle:checkstyle -Dcheckstyle.includes=**\/SystemConfig*.java

Logging

We have adopted a pattern where the top of every class file has a line like this:

private static final Logger logger = Logger.getLogger(DatasetUtil.class.getCanonicalName());

Use this logger field with varying levels such as fine or info like this:

logger.fine("will get thumbnail from dataset logo");

Generally speaking you should use fine for everything that you don’t want to show up in Glassfish’s server.log file by default. If you use a higher level such as info for common operations, you will probably hear complaints that your code is too “chatty” in the logs. These logging levels can be controlled at runtime both on your development machine and in production as explained in the Debugging section.

When adding logging, do not simply add System.out.println() lines because the logging level cannot be controlled.

Bash

Generally, Google’s Shell Style Guide at https://google.github.io/styleguide/shell.xml seems to have good advice.

Formatting Code

Tabs vs. Spaces

Don’t use tabs. Use 2 spaces.

shfmt from https://github.com/mvdan/sh seems like a decent way to enforce indentation of two spaces (i.e. shfmt -i 2 -w path/to/script.sh) but be aware that it makes other changes.

Previous: Debugging | Next: Deployment