### Question:
OAuthClientDetailsService { public void encodeClientSecret(OAuthClientDetails oauthClientDetails) { oauthClientDetails.setClientSecret( passwordEncoder.encode(oauthClientDetails.getClientSecret())); }  void fillDefaultValues(OAuthClientDetails oauthClientDetails); void encodeClientSecret(OAuthClientDetails oauthClientDetails); OAuthClientDetails getOAuthClientDetails(); void updateOAuthClientDetails(OAuthClientDetails oauthClientDetails);  }### Answer:
@Test public void encodeClientSecret_encodesSecret() { oauthClientDetails.setClientSecret("Test123"); oauthClientDetailsService.encodeClientSecret(oauthClientDetails); assertEquals("Encoded String", oauthClientDetails.getClientSecret()); }