@Test
    public void testMissingFieldsOk() {
        val client = new OkClient();
        client.setKey(KEY);
        client.setSecret(SECRET);
        client.setCallbackUrl(CALLBACK_URL);
        client.setPublicKey(null);
        TestsHelper.initShouldFail(client, "publicKey cannot be blank");
    }
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