Environment

When important data is written to STDIN/STDOUT and an application relies on specific system properties or environment variables, writing tests is getting more complicated. System Rules is a collection of JUnit rules that helps us writing Java tests for everything that deals with java.lang.System. In the following short examples I’d like to demonstrate how to deal with system properties, environment variables, STDOUT and STDERR and capturing both for testing e.g. for some golden master refactoring. ...

There’s a variety of configuration frameworks to use in our Java applications. Java Config Builder is one of them and it offers some nice features that I would like to demonstrate in the following short examples as are: Loading values from different sources like property-files, environment variables, command-line-arguments or system properties, specifying default values, mapping arbitrary types or collections, merging configurations and using the Java Bean Validation standard aka JSR-303. ...

These are not only linux snippets but also bash snippets and snippets using tools that run under Linux, *nix or sometimes even MacOSX, I should reorder this article someday ;) Settings for more reliable bash scripts set -euo pipefail this gives us …​ -e: exit script if a single command fails -u: exit script if an unset variable is used -o pipefail: return value of a pipeline is the status of the last command to exit with a non-zero status, or zero if no command exited with a non-zero status ...

Define and Configure Log Groups This allows to configure a group of loggers at the same time Define a log group named myaspect with two packages application.properties logging.group.myaspect=com.hascode.package1,com.hascode.package2 Configure the log group and set all loggers to level TRACE application.properties logging.level.myaspect=TRACE This is also possible as parameter on startup java -Dlogging.level.myaspect=TRACE myapp.jar Use JUnit 5 with Spring Boot Use newer versions of Surefire and Failsafe plugins: <properties> [..] <maven-failsafe-plugin.version>2.22.0</maven-failsafe-plugin.version> <maven-surefire-plugin.version>2.22.0</maven-surefire-plugin.version> </properties> ...