@BeforeClass
    public static void setUpCredentials() {
        if (credentials == null) {
            try {
                credentials = chain.getCredentials();
            } catch (Exception ignored) {
            }
        }
    }
Before of super class is guaranteed to be called before that of a subclass so the following
is safe. http://junit-team.github.io/junit/javadoc/latest/org/junit/Before.html
aws-java-sdk-test-utils/src/main/java/com/amazonaws/test/AWSIntegrationTestBase.java