In JUnit 5, how to run code before all tests

Question

The @BeforeAll annotation marks a method to run before all tests in a class.

http://junit.org/junit5/docs/current/user-guide/#writing-tests-ann

Answer 1

You can mark each of your test classes that uses your database with an interface that defines a static BeforeAll (so that it cannot be overridden). e.g.:

interface UsesDatabase {
    @BeforeAll
    static void initializeDatabaseConnections() {
        // initialize database connections
    }
}

This method will be invoked once for each implementing class so you will need to define a way to initialize your connections only once and then do nothing for the other calls.