private OAuth20Client getClient() {
        val client = new GitHubClient();
        client.setKey(KEY);
        client.setSecret(SECRET);
        client.setCallbackUrl(CALLBACK_URL);
        return client;
    }
This class tests the {@link OAuth20Client} class.

@author Jerome Leleu
@since 1.0.0
pac4j-oauth/src/test/java/org/pac4j/oauth/client/OAuth20ClientTests.java