@Test
    void verifyNoSigningKey() throws Throwable {
        val service = getOidcRegisteredService("whatever");
        service.getProperties().put(RegisteredServiceProperties.ACCESS_TOKEN_AS_JWT_SIGNING_ENABLED.getPropertyName(),
            new DefaultRegisteredServiceProperty(RegisteredServiceProperties.ACCESS_TOKEN_AS_JWT_SIGNING_ENABLED.getDefaultValue()));

        val key = EncodingUtils.generateJsonWebKey(512);
        service.getProperties().put(RegisteredServiceProperties.ACCESS_TOKEN_AS_JWT_SIGNING_KEY.getPropertyName(),
            new DefaultRegisteredServiceProperty(key));
        val at = getAccessToken(service.getClientId());
        val encoded = oidcRegisteredServiceJwtAccessTokenCipherExecutor.encode(at.getId(), Optional.of(service));
        assertNotNull(encoded);
    }
This is {@link OidcRegisteredServiceJwtAccessTokenCipherExecutorTests}.

@author Misagh Moayyed
@since 6.1.0
support/cas-server-support-oidc/src/test/java/org/apereo/cas/oidc/token/OidcRegisteredServiceJwtAccessTokenCipherExecutorTests.java